https://ja.wikipedia.org/wiki/PostPet( https://ja-m-wikipedia-org.translate.goog/wiki/PostPet?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en-US&_x_tr_pto=wapp )https://everything2.com/title/PostPet( https://www.so-net.ne.jp/postpet/ )