| Step | Hyp | Ref | Expression | 
						
							| 1 |  | f1od.1 |  |-  F = ( x e. A |-> C ) | 
						
							| 2 |  | f1od.2 |  |-  ( ( ph /\ x e. A ) -> C e. W ) | 
						
							| 3 |  | f1od.3 |  |-  ( ( ph /\ y e. B ) -> D e. X ) | 
						
							| 4 |  | f1od.4 |  |-  ( ph -> ( ( x e. A /\ y = C ) <-> ( y e. B /\ x = D ) ) ) | 
						
							| 5 | 2 | ralrimiva |  |-  ( ph -> A. x e. A C e. W ) | 
						
							| 6 | 1 | fnmpt |  |-  ( A. x e. A C e. W -> F Fn A ) | 
						
							| 7 | 5 6 | syl |  |-  ( ph -> F Fn A ) | 
						
							| 8 | 3 | ralrimiva |  |-  ( ph -> A. y e. B D e. X ) | 
						
							| 9 |  | eqid |  |-  ( y e. B |-> D ) = ( y e. B |-> D ) | 
						
							| 10 | 9 | fnmpt |  |-  ( A. y e. B D e. X -> ( y e. B |-> D ) Fn B ) | 
						
							| 11 | 8 10 | syl |  |-  ( ph -> ( y e. B |-> D ) Fn B ) | 
						
							| 12 | 4 | opabbidv |  |-  ( ph -> { <. y , x >. | ( x e. A /\ y = C ) } = { <. y , x >. | ( y e. B /\ x = D ) } ) | 
						
							| 13 |  | df-mpt |  |-  ( x e. A |-> C ) = { <. x , y >. | ( x e. A /\ y = C ) } | 
						
							| 14 | 1 13 | eqtri |  |-  F = { <. x , y >. | ( x e. A /\ y = C ) } | 
						
							| 15 | 14 | cnveqi |  |-  `' F = `' { <. x , y >. | ( x e. A /\ y = C ) } | 
						
							| 16 |  | cnvopab |  |-  `' { <. x , y >. | ( x e. A /\ y = C ) } = { <. y , x >. | ( x e. A /\ y = C ) } | 
						
							| 17 | 15 16 | eqtri |  |-  `' F = { <. y , x >. | ( x e. A /\ y = C ) } | 
						
							| 18 |  | df-mpt |  |-  ( y e. B |-> D ) = { <. y , x >. | ( y e. B /\ x = D ) } | 
						
							| 19 | 12 17 18 | 3eqtr4g |  |-  ( ph -> `' F = ( y e. B |-> D ) ) | 
						
							| 20 | 19 | fneq1d |  |-  ( ph -> ( `' F Fn B <-> ( y e. B |-> D ) Fn B ) ) | 
						
							| 21 | 11 20 | mpbird |  |-  ( ph -> `' F Fn B ) | 
						
							| 22 |  | dff1o4 |  |-  ( F : A -1-1-onto-> B <-> ( F Fn A /\ `' F Fn B ) ) | 
						
							| 23 | 7 21 22 | sylanbrc |  |-  ( ph -> F : A -1-1-onto-> B ) | 
						
							| 24 | 23 19 | jca |  |-  ( ph -> ( F : A -1-1-onto-> B /\ `' F = ( y e. B |-> D ) ) ) |