let S, T be non empty TopSpace; for s being Point of
for t being Point of holds pi_1 [:S,T:],[s,t], product <*(pi_1 S,s),(pi_1 T,t)*> are_isomorphic
let s be Point of ; for t being Point of holds pi_1 [:S,T:],[s,t], product <*(pi_1 S,s),(pi_1 T,t)*> are_isomorphic
let t be Point of ; pi_1 [:S,T:],[s,t], product <*(pi_1 S,s),(pi_1 T,t)*> are_isomorphic
take
FGPrIso s,t
; GROUP_6:def 15 FGPrIso s,t is bijective
thus
FGPrIso s,t is bijective
by Th29; verum