7. Manner of proving payment of tax by the contractor and the principal or the commission agent-

(1) A claim made by a contractor under clause (b) of sub-section (1) of section 6 shall be supported by a declaration in form 3 to be issued by the sub-contractor and shall be admitted in proof of such claim.

(2) A claim made by a principal under sub-clause (i) of clause (b) of sub-section (2) of section 6 shall be supported by an adat patti or sale account issued by the commission agent in accordance with the system prevalent in the market and shall be admitted in proof of such claim.

(3) A claim made by a commission agent under sub-clause (ii) of clause (b) of sub-section (2) of section 6 shall be supported by a declaration in form 4 issued by the principal and shall be admitted as proof in support of such claim.