J. Balogh, Identification keys of world oribatid (Acari) families and genera ACTA ZOOL. ACAD. SCI. HUNG.,
7(3-4): 243-344, 1961.
The download button generates a pdf of the user-selected pages on command. It is a long article resulting in a huge (>100 MB) pdf. I found it necessary to download it in three parts and concatonate with Adobe Pro to avoid time-out errors. Adobe Pro's Document/Reduce File Size function can then be used to drammatically reduce the size of the final document, with no obvious loss of image quality.
Full text