from good hands
have something on good authority
springhead
confirmatively
bankable
authority
trusted
unsupported
dead-on
probably
in all likelihood
in all probability
likely
belike
truth
reliably
right as rain
to a nicety
straight from the horse's mouth
honest
dead on
on target
unerring
unmistaken
copper-bottomed
reputably
precise
hyperaccurate
factful
unsuspect
safe
verifiably
intersource
corroboratively
speak by the card
up to the knocker
steady-handed
right
veracious
superaccurate
positively
credibly
crisp
surgical
steady as a rock
ultrareliable
aright
plausible
correctly
provably