On some geometric properties and applications of conformal rational transformations in a plane (1912)
Renich, Mary Emma · leaf 50
+ c*(t8 - 12 iab - 2a8 + 2b8)(a8 - b8 - 2iab) x ■ a* -*T^~ST^ Ycf (ib t a) ) + 1{** - b» - 2iab) ■ 0, (10) a biquadratic in c. Hence there are four tangents from I to thecubic. Likewise there are four from I • The intersections of 2 these two pencils of tangents give the l6 foci , only four being…
