(a) The secretary of state and each county clerk shall keep an alphabetical index of:
(1) all assumed names that have been filed in the office of the respective officer; and
(2) the persons filing the certificates.
(b) A copy of a certificate or statement is presumptive evidence in any court in this state of the facts contained in the copy if the copy is certified to by:
(1) the county clerk in whose office the certificate or statement was filed; or
(2) the secretary of state.