Let ABC be a triangle. Ac,Bc lie on AB; Ba,Ca lie on BC; Cb,Ab
lie on AC. Such that (BBaBc), (CCaCb), (AAbAc) tangent with (ABC)
BcBa meets CaCb at A'; BcBa meets AcAb at C'. AcAb meets CbCa at B'.
1-(C'BcAc) tangent with (A'B'C') , (BBcBa), (AAcAb)
2-BB',AA',CC' are concurrent at D
3-Oa,O'a are center of (AAcAb) and (A'BaCa) respectively.
Denote Oc, O'c; Ob,O'b cyclically then OaO'a; ObO'b; OcO'c
are concurrent at E
4-O,O' are center of (ABC) and (A'B'C'). Then O,O',D,E collinear
