ころころコロニャ : 3匹のねこと時々しばいぬ
ころころ ころにゃ : さんびき の ねこ と ときどき しばいぬ
est. Rough estimate based on volume count, reprints and magazine — not an official figure
External databases: MADB
How to compare editions, collected volumes and ISBNs / Sources, updates and corrections