Section 25 of the Principal Act is hereby amended -
(a) in subsection (1) by the insertion after paragraph (aa) (inserted by the Act of 1991) of the following paragraph:
"(ab) the deeming, in accordance with section 37, of a person to have made supplies in the course or furtherance of business,",
and
(b) in subsection (2) by the substitution of "section 11 (1B), 23 or 23A" for "section 11(1B) or 23".