4 cikk fénymásolata egybekötve...#1: A. Earl Pritchard; Edward W. Baker: The false spider mites of California (Acarina: Phytoptipalpidae) [University of California Publications in Entomology 1952/9. évf. 1. sz., pp. 1-94, 45 ábra]..#2: A. Earl Pritcahrd; Edward W. Baker: The false spider mites (Acarina: Tenuipalpidae) [University of California Publications in Entomology 1958/14. évf. 3. sz., pp. 175-274, 51 szövegközi ábra]..#3: H. H. J. Nesbitt: A taxonomic study of the Phytoseiinae (Family Laelaptidae) Predaceous upon Tetranychidae of economic importance [Zoologische Verhandelingen 1951/12. sz., pp. 1-64, 32 tábla]..#4: C. V. G. Morgan; N. H. Anderson: Bryobia arborea n. sp. and Morphological Characters Distinguishing It from B. praetiosa Koch (Acarina: Tetranychidae) [The Canadian Entomologist 1957/89. évf. 11. sz., pp.485-490]..Szakjel: 595 C21..Angol nyelv?