Assessment powers under commodities transaction tax: officer may require documents and determine tax with a statutory assessment time limit. The Assessing Officer may require any assessee who furnished a return under section 107 or who received a notice thereunder to produce accounts, documents or other evidence, and may serve further notices for additional material. After considering such material and any other relevant material, the officer shall, by written order, assess transaction values and determine commodities transaction tax payable or refundable, subject to a two-year statutory limitation from the end of the relevant financial year; refundable amounts must be returned to the seller or purchaser within the prescribed time.