Japan : an illustrated encyclopedia, Kodansha, 1993: p. 412 (Pen name used for joint projects by the cartoonists Fujimoto Hiroshi (b. 1933) and Abiko Motoo (b. 1934) ...)
Manga, Taschen, 2004: p. 428 (Hiroshi Fujimoto and Motoo Abiko ended their creative collaboration under the name of Fujiko Fujio in 1987, when each of them went off to pursue their own careers)