substantiated (adj.)

• actual
• ascertained
• attested
• authenticated
• certain
• certified
• confirmed
• corroborated
• demonstrated
• determined
• documentary
• effectual
• established
• factual
• fixed
• historical
• proved
• proven
• real
• settled
• sure-enough
• true
• truthful
• unquestionable
• validated
• veracious
• verified
• veritable