Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Breton
bemdez
←
Breton
*beu-
(mention)
←
Breton
deiz
(mention)
←
Welsh
pob
(cognate)
←
Welsh
obeutu
(mention)
←
Welsh
beunydd
(cognate)
→
Welsh
obeutu
(cognate)