| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ernggrp.h |  | 
						
							| 2 |  | ernggrp.d |  | 
						
							| 3 |  | erngdv.b |  | 
						
							| 4 |  | erngdv.t |  | 
						
							| 5 |  | erngdv.e |  | 
						
							| 6 |  | erngdv.p |  | 
						
							| 7 |  | erngdv.o |  | 
						
							| 8 |  | erngdv.i |  | 
						
							| 9 |  | eqid |  | 
						
							| 10 | 1 4 5 2 9 | erngbase |  | 
						
							| 11 | 10 | eqcomd |  | 
						
							| 12 |  | eqid |  | 
						
							| 13 | 1 4 5 2 12 | erngfplus |  | 
						
							| 14 | 6 13 | eqtr4id |  | 
						
							| 15 | 1 2 3 4 5 6 7 8 | erngdvlem1 |  | 
						
							| 16 | 1 4 5 6 | tendoplcom |  | 
						
							| 17 | 11 14 15 16 | isabld |  |