Nijiumu were Asahito Nanjo, Keiji Haino, Shizuo Uchida and Tetuzi Akiyama. If you don't count the live set on the Driftworks release, I'm pretty sure that this was their only official release and that Asahito had left by this point. Regardless, this is a truly cavernous and atmospheric work of wonder!
Released on P.S.F. Records in 1993.
Whilst I'm here, in case you weren't around at the time, I've re-upped both of the La Musica CDrs, the Driftworks box-set and (for good measure) the two Aihiyo releases.