| Step | Hyp | Ref | Expression | 
						
							| 1 |  | m.b |  | 
						
							| 2 |  | m.m |  | 
						
							| 3 |  | m.z |  | 
						
							| 4 |  | m.a |  | 
						
							| 5 |  | ollat |  | 
						
							| 6 | 5 | 3ad2ant1 |  | 
						
							| 7 |  | simp2 |  | 
						
							| 8 |  | simp3 |  | 
						
							| 9 | 1 4 | atbase |  | 
						
							| 10 | 8 9 | syl |  | 
						
							| 11 |  | eqid |  | 
						
							| 12 | 1 11 2 | latmle2 |  | 
						
							| 13 | 6 7 10 12 | syl3anc |  | 
						
							| 14 |  | olop |  | 
						
							| 15 | 14 | 3ad2ant1 |  | 
						
							| 16 | 1 2 | latmcl |  | 
						
							| 17 | 6 7 10 16 | syl3anc |  | 
						
							| 18 | 1 11 3 4 | leatb |  | 
						
							| 19 | 15 17 8 18 | syl3anc |  | 
						
							| 20 | 13 19 | mpbid |  |