por Adair, John, 1913- [autor] | Villamizar Herrera, Jesús [traductor] | Serna Gómez, Humberto [colaborador] | Adair, John, 1913-. Art of creative thinking.
por Adair, John, 1913- [autor] | Niño Torres, Teresa [traductor] | Serna Gómez, Humberto [colaborador] | Adair, John, 1913-. How to manage your time.