(a) For the purpose of the proper administration of this chapter and to prevent evasion of the tax imposed hereunder, it shall be presumed that tangible personal property or services sold by any person for delivery in the commonwealth is sold for storage, use or other consumption in the commonwealth until the contrary is established. The burden of proving the contrary is upon the person who makes the sale unless he takes from the purchaser a certificate to the effect that the service or property is purchased for resale and such certificate is received and made available to the commissioner not later than sixty days from the date of notice from the commissioner to produce such certificate. Where a certificate is deficient in some material manner and where such deficiency is thereafter removed, also within said sixty day period, the receipt of such certificate shall be deemed to have satisfied the foregoing time limit.

[There is no paragraph (b).]