Furuyama Kazunari

At one time an insei in Japan, he researched extensively and provided all his materials for Get Strong at Joseki.

According to the AGEJ, he is now active as a Go teacher.

Publishes lessons in the AGA journal. On page 80 of the 2004 American Go Yearbook, his column 'Fundamental Matters' (tesuji 208) mentions "the ten worst mistakes". I am curious what this list includes besides the one pointed out in the article... I've never heard of "the ten worst mistakes" before.

Private lessons are available on his web site , blog , and blog.