Gotthard Weise, Cevian projections of inscribed triangles and generalized Wallace lines,
Forum Geometricorum, 16 (2016) 241--248.

Abstract. Let Delta = ABC be a reference triangle and Delta' = A'B'C' an inscribed triangle of Delta. We define the cevian projection of Delta' as the cevian triangle Delta_P of a certain point P. Given a point P not on a sideline, all inscribed triangles with common cevian projection Delta_P form a family D_P = {Delta(t) = A_tB_tC_t, t in R}. The parallels of the lines AA_t, BB_t, CC_t through any point of a certain circumconic C_P intersect the sidelines a, b, c in collinear points X, Y, Z, respectively. This is a generalization of the well-known theorem of Wallace.

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