Fantastic book...I own it myself, although I paid 100 (with shipping) lol. Be prepared though, it definitely follows the Japanese ethos of tank sizing, ie really small.
It quotes a 90cm Heterotis niloticus needing a 90-120cm tank...
Sort of confusing layout, it presents all the families of Osteoglossimorpha (knives, arowanas, mormyrids, etc), followed by their care...then give you the "other" primitive fish (lungs, rays, sturgeon, bichirs, etc) and care.
Awesome pick up, especially as it's out of print.