SPICE System Overview (in Russian) (file naifov_r.doc),
The following SPICE System description documents in WinWord 6.0 format are available from Mars-96 SPICE Data Archive via anonymous FTP:
SPICE System Overview (in Russian) (file naifov_r.doc),
Most Used SPICELIB Subroutines (in Russian) (file naifqr_r.doc),
SPICE System Overview (in English) (file naifov_e.doc),
Most Used SPICELIB Subroutines (in English) (file naifqr_e.doc).
These documents are located in the directory pub/naif/doc