springhead
mother
ur-source
straight from the horse's mouth
root
emanate
from good hands
firsthand
at first hand
give birth
reference
trufax
authorship
have something on good authority
title
last word
underpinning
founded
outpart
oroclinal
scripture
fons et origo
magisterium
factually
forenote
factualist
wartweed
uredineous
uredinous
intersource
afore-explained
prediscovery
guest
uredosporic
uredosporous
factically
by
foundation stone
font
meat and potatoes
straight
grass roots
issuing
acceptable
rise
relevantly
⠁⠉
clue
foretalk
abovestated