| Step | Hyp | Ref | Expression | 
						
							| 0 |  | cA |  |-  A | 
						
							| 1 | 0 | wsmo |  |-  Smo A | 
						
							| 2 | 0 | cdm |  |-  dom A | 
						
							| 3 |  | con0 |  |-  On | 
						
							| 4 | 2 3 0 | wf |  |-  A : dom A --> On | 
						
							| 5 | 2 | word |  |-  Ord dom A | 
						
							| 6 |  | vx |  |-  x | 
						
							| 7 |  | vy |  |-  y | 
						
							| 8 | 6 | cv |  |-  x | 
						
							| 9 | 7 | cv |  |-  y | 
						
							| 10 | 8 9 | wcel |  |-  x e. y | 
						
							| 11 | 8 0 | cfv |  |-  ( A ` x ) | 
						
							| 12 | 9 0 | cfv |  |-  ( A ` y ) | 
						
							| 13 | 11 12 | wcel |  |-  ( A ` x ) e. ( A ` y ) | 
						
							| 14 | 10 13 | wi |  |-  ( x e. y -> ( A ` x ) e. ( A ` y ) ) | 
						
							| 15 | 14 7 2 | wral |  |-  A. y e. dom A ( x e. y -> ( A ` x ) e. ( A ` y ) ) | 
						
							| 16 | 15 6 2 | wral |  |-  A. x e. dom A A. y e. dom A ( x e. y -> ( A ` x ) e. ( A ` y ) ) | 
						
							| 17 | 4 5 16 | w3a |  |-  ( A : dom A --> On /\ Ord dom A /\ A. x e. dom A A. y e. dom A ( x e. y -> ( A ` x ) e. ( A ` y ) ) ) | 
						
							| 18 | 1 17 | wb |  |-  ( Smo A <-> ( A : dom A --> On /\ Ord dom A /\ A. x e. dom A A. y e. dom A ( x e. y -> ( A ` x ) e. ( A ` y ) ) ) ) |