Complex sentence: The history of the document is relatively complex, as numerous individuals were involved, and at different times, spawning two distinct notebooks, which were translated into multiple languages, Carrier, Richard (2002).
Split into simpler sentences: The history of the document is relatively complex, as numerous individuals were involved, working at different times, collating different parts of the work. This effort spawned two distinct notebooks, which were translated into multiple languages, Carrier, Richard (2002).