[This needs to become an overview suitable for reference in all wikipedia articles on NABBP players and clubs.]
Marshall Wright (NABBP, 1857-1870 (McFarland 2002)) is essentially a compilation of facts similar to the team-season pages of the Retrosheet website, the so-called Complete Rosters and Game Logs example: 1877 Cincinnati Red Stockings. There is very little prose in the book, about three introductory pages for each year. Meanwhile there must be 10,000 lines like these two for the Buckeye club of Cincinnati in 1867 (page 165, with their headings).
- DATE, OPPONENT, SCORE, W L T
- 10/19, Cincinnati (Cincinnati), 23 37, L
October 19, 1867, the Buckeye club met the Cincinnati club of Cincinnati and lost 23-37.
- BATTER, POS, GP, HL, R
- Charles Gould, 1B, 13, 32 60
Charles Gould played 13 games during that Buckeye season, mainly or only fielding firstbase. He was put out 32 times and he scored 60 runs.
Almost every fact should be understood with qualifications such as "known games" or "games known by Wright" or "known matches with NABBP members known by Wright, reported in box scores known by Wright".
Some other sources mention some player-team affiliations but known is or tries to be as complete, whose completeness is limited by what fits in the book as well as by what he knows. He has not distributed the database (which is partly manuscript and photocopy, I suppose). The book gives more important team-seasons and for most seasons gives only the five-game men, approximately, for the team-seasons that it covers.