For "pseudo-triangle" see, e.g.,
Whitehead, J. H. C. (1961), "Manifolds with transverse fields in Euclidean space", Annals of Mathematics, 73 (1): 154–212, doi:10.2307/1970286, JSTOR1970286, MR0124917.
On page 196 this paper refers to a "pseudo-triangle condition" in functional approximation. For "pseudo-triangulation" see, e.g., Belaga, È. G. (1976), "[Heawood vectors of pseudotriangulations]", Doklady Akademii Nauk SSSR (in Russian), 231 (1): 14–17, MR0447029.
For "pseudo-triangle" see, e.g.,
Whitehead, J. H. C. (1961), "Manifolds with transverse fields in Euclidean space", Annals of Mathematics, 73 (1): 154–212, doi:10.2307/1970286, JSTOR1970286, MR0124917.
On page 196 this paper refers to a "pseudo-triangle condition" in functional approximation. For "pseudo-triangulation" see, e.g., Belaga, È. G. (1976), "[Heawood vectors of pseudotriangulations]", Doklady Akademii Nauk SSSR (in Russian), 231 (1): 14–17, MR0447029.
For "pseudo-triangle" see, e.g.,
Whitehead, J. H. C. (1961), "Manifolds with transverse fields in Euclidean space", Annals of Mathematics, 73 (1): 154–212, doi:10.2307/1970286, JSTOR1970286, MR0124917.
On page 196 this paper refers to a "pseudo-triangle condition" in functional approximation. For "pseudo-triangulation" see, e.g., Belaga, È. G. (1976), "[Heawood vectors of pseudotriangulations]", Doklady Akademii Nauk SSSR (in Russian), 231 (1): 14–17, MR0447029.