of the Pentax K-mount, PentaxForums Pentax K-mount page, KMP (former Bojidar Dimitrov) Pentax K Lens Database, Aperturepedia. A comprehensive table with detailed information on all first-party Pentax K-mount lenses Pentax K-Mount Lenses Explained, Mosphotos.com Pentax Lens Compatibility Chart, Mosphotos.com Pentax Lens Review Database and Third-Party PK-mount Lens Review Database, PentaxForums The Pentax Lens Gallery: List of some film-era Pentax K lenses and some comparison on bokeh and flare, also selected non-Pentax ones Pentax DSLR lenses catalog, Pentax UK The PENTAX optical system - Magical moments captured in detail and clarity, archived Pentax lens product page Stan's Pentax Photography, Stan Halpin Lens mounts K-mount Japanese inventions