Koi farming as side-business for farmers - The Original.
We present here a historical document that should interest all koi keepers. This is a bonus for all locked-down koi keepers.
Koshida, Shuho. 1931. Fish farming as side-business for farmers. Niigata Farmers Association. Japan. p. 120 [in Japanese] pp. 98-117. Original translation by Naoko Mizoguchi, 2007. Edited by Servaas de Kock and Ronnie Watt. Appendix to the book Koi Culture
Servaas de Kock