Giovanni Battista Martini: Detailed biography with portrait and internal links to related people and his musical period from the Here Of A Sunday Morning radio program.
Giovanni Battista Martini: Wikipedia article originally from the 1911 Encyclopedia Britannica with portrait and links.
Martini, Padre Giovanni Battista: Brief biography with summary of works and overview of achievements from the Grove Concise Dictionary of Music entry at WQXR radio.