AMERICAN CINEMATOGRAPHERS MANUAL

All film cameras operate essentially the same. What works on one usually works with all. The setting of the ASA speeds, shutter angle, f-stops, etc, is the same with the Bolex 8mm series as it is for most all other 8mm, 16mm, 35mm,  and 70mm film cameras. Good thing, too. Lots of information freely available online and published.

The ASC  "American Cinematographers Manual" is the standard. There are actually 2 manuals now. The film and the newer video manual. You'll want the film:

http://www.ebay.com/sch/i.html?_nkw=american+cinematographer+manual&_sacat=0&_odkw=american+cinematographer&_osacat=0&_from=R40&LH_Complete=1

I looked. There are a few there. Both new and used. These used to typically sell for $5-$10 used, but have become somewhat scarce in the last few years. 

See also amazon:

http://www.amazon.com/s/ref=nb_sb_noss_1/178-7937462-9884824?url=search-alias%3Daps&field-keywords=american+cinematographers+manual

The manuals are updated every couple of years or so. The manuals typically cover the cameras used in that previous period. The 5th edition even covers Bolex 16mm cameras!

These are the topics from the index of the "American Cinematographers Manual", 5th edition, 626 pages, 1980:

Cameras 65mm
Cameras 35mm
Cameras 16mm
Film Stock
Lenses
Lighting
Exposure Filter
Miscellaneous equipment
Sound
Lab Procedures
Special Effects Photography
Special Techniques.

No 8mm material, but a lot of charts, graphs, and picture of old film equipment, etc, but still very much useful for the 8mm cinematographer.