<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>0026 - Disclosure - 18a. INCOME TAXES</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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</LabelSeparator><Level>1</Level><ElementName>us-gaap_IncomeTaxDisclosureAbstract</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText /><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>xbrli:stringItemType</ElementDataType><SimpleDataType>string</SimpleDataType><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Income Tax Disclosure [Abstract]</Label></Row><Row FlagID="0"><Id>2</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>
</LabelSeparator><Level>2</Level><ElementName>us-gaap_IncomeTaxDisclosureTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="From2011-10-01to2012-09-30" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The Company has incurred losses since inception, which have generatednet operating loss carryforwards.&amp;#160;&amp;#160;The net operating loss carryforwards arise from United States sources.&amp;#160;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Pretax losses arising from United States operations were approximately
$1,522,000 for the year ended September 30, 2012. Pretax losses arising from United States operations were approximately $2,534,000
for the year ended September 30, 2011. &amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The Company has non- US net operating loss carryforwards of approximately
$11,877,200, which expire in 2019-2030 and US of approximately $11,877,200 which expire in 2019-2030. Because it is not more likely
than not that sufficient tax earnings will be generated to utilize the net operating loss carryforwards, a corresponding valuation
allowance of approximately $1,164,000 and $1,151,000 was established as of September 30, 2012 and 2011, respectively. Additionally,
under the Tax Reform Act of 1986, the amounts of, and benefits from, net operating losses may be limited in certain circumstances,
including a change in control.&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Section&amp;#160;382 of the Internal Revenue Code generally imposes an
annual limitation on the amount of net operating loss carryforwards that may be used to offset taxable income when a corporation
has undergone significant changes in its stock ownership. There can be no assurance that the Company will be able to utilize any
net operating loss carryforwards in the future.&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;For the year ended September 30, 2012, the Company&amp;#146;s effective
tax rate differs from the federal statutory rate principally due to net operating losses and warrants issued for services.&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0"&gt;The principal components of the Company&amp;#146;s deferred tax assets
at September 30, 2012 are as follows:&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;table align="center" cellspacing="0" cellpadding="0" style="font: 8pt Times New Roman, Times, Serif; width: 100%"&gt;
&lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;2012&lt;/td&gt;
    &lt;td nowrap="nowrap" style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;2011&lt;/td&gt;
    &lt;td nowrap="nowrap" style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;
    &lt;td style="width: 64%"&gt;U.S. operations loss carry forward at statutory rate of 42.6%&lt;/td&gt;
    &lt;td style="width: 1%; text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="width: 1%"&gt;$&lt;/td&gt;
    &lt;td style="width: 15%; text-align: right"&gt;(1,163,832&lt;/td&gt;
    &lt;td nowrap="nowrap" style="width: 1%"&gt;)&lt;/td&gt;
    &lt;td style="width: 1%; text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="width: 1%"&gt;$&lt;/td&gt;
    &lt;td style="width: 15%; text-align: right"&gt;(1,151,090&lt;/td&gt;
    &lt;td nowrap="nowrap" style="width: 1%"&gt;)&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: white"&gt;
    &lt;td&gt;Less Valuation Allowance&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;1,163,832&lt;/td&gt;
    &lt;td nowrap="nowrap"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;1,151,090&lt;/td&gt;
    &lt;td nowrap="nowrap"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;Net Deferred Tax Assets&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;-&lt;/td&gt;
    &lt;td nowrap="nowrap" style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;-&lt;/td&gt;
    &lt;td nowrap="nowrap" style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: white"&gt;
    &lt;td style="padding-bottom: 3pt"&gt;Change in Valuation allowance&lt;/td&gt;
    &lt;td style="padding-bottom: 3pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 2.25pt double"&gt;$&lt;/td&gt;
    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;-&lt;/td&gt;
    &lt;td nowrap="nowrap" style="padding-bottom: 3pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="padding-bottom: 3pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 2.25pt double"&gt;$&lt;/td&gt;
    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;-&lt;/td&gt;
    &lt;td nowrap="nowrap" style="padding-bottom: 3pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;
&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;A reconciliation of the United States Federal Statutory rate to the
Company&amp;#146;s effective tax rate for the period ended September 30, 2012 and 2011 is as follows:&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;table align="center" cellspacing="0" cellpadding="0" style="font: 8pt Times New Roman, Times, Serif; width: 100%"&gt;
&lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;2012&lt;/td&gt;
    &lt;td nowrap="nowrap" style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;2011&lt;/td&gt;
    &lt;td nowrap="nowrap" style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;
    &lt;td style="width: 64%"&gt;Federal Statutory Rate&lt;/td&gt;
    &lt;td style="width: 1%; text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="width: 15%; text-align: right"&gt;-42.6&lt;/td&gt;
    &lt;td nowrap="nowrap" style="width: 1%"&gt;%&lt;/td&gt;
    &lt;td style="width: 1%; text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="width: 15%; text-align: right"&gt;-42.6&lt;/td&gt;
    &lt;td nowrap="nowrap" style="width: 1%"&gt;%&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: white"&gt;
    &lt;td&gt;Increase in Income Taxes Resulting from:&lt;/td&gt;
    &lt;td&gt;&amp;#160;&lt;/td&gt;
    &lt;td&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td nowrap="nowrap"&gt;&amp;#160;&lt;/td&gt;
    &lt;td&gt;&amp;#160;&lt;/td&gt;
    &lt;td&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td nowrap="nowrap"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;Change in Valuation allowance&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;42.6&lt;/td&gt;
    &lt;td nowrap="nowrap" style="padding-bottom: 1.5pt"&gt;%&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;42.6&lt;/td&gt;
    &lt;td nowrap="nowrap" style="padding-bottom: 1.5pt"&gt;%&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: white"&gt;
    &lt;td style="padding-bottom: 3pt"&gt;Effective Tax Rate&lt;/td&gt;
    &lt;td style="padding-bottom: 3pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 2.25pt double"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;0.0&lt;/td&gt;
    &lt;td nowrap="nowrap" style="padding-bottom: 3pt"&gt;%&lt;/td&gt;
    &lt;td style="padding-bottom: 3pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 2.25pt double"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;0.0&lt;/td&gt;
    &lt;td nowrap="nowrap" style="padding-bottom: 3pt"&gt;%&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;
&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0"&gt;The Company evaluated subsequent events, for the purpose of adjustment
or disclosure, up through the date the financial statements were issued.&lt;/p&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

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