Plane and spherical trigonometry - Sarmiento, Agnes Cenen E.; Calilung, Joseph M.; Sadac, Grace C.; Sales, Valentino S.; Lingat, Nelson G.; Limin, Antonio Valer R.; Chavez, MIchael M.; Guzman, Danilo M. Jr. (Mandaluyong Books Atbp. Publishing Corp., 2009)
Keywords: Trigonometry -- Problems, exercises, etc; Spherical trigonometry -- Problems, exercises, etc