1) Collateral 2) Confirmatory 3) Confirming 4) Corroborative 5) Corroboratory 6) Substantiating 7) Substantiative 8) Supportive 9) Validating 10) Validatory 11) Verificatory 12) Verifying 1) Confirmatory 2) Corroborative 3) Corroboratory 4) Substantiating 5) Substantiative 6) Supportive 7) Validating 8) Validatory 9) Verificatory 10) Verifying 
• (a.) Tending to confirm or establish.
Con·firm'a·tive adjective [ Latin confirmativus : confer French confirmatif .] Tending to confirm or establish. Sherwood. --