From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
Isamu Tanonaka (田の中 勇, Tanonaka Isamu) (July 19, 1932 - January 13, 2010) was a Japanese voice actor from Taitō, Tokyo, Japan. During his life, he had been attached to Gekidan Tōgei and Theatre Echo. He was attached to Aoni Production at the time of his death.
He voiced Gala in the Japanese dub of Dr. Slump and Dragon Ball, Dr. Raichi in Dragon Ball Z Gaiden: Saiya-jin Zetsumetsu Keikaku, and Bibidi and Raiti in Dragon Ball Z.