Wouters, J., & Verhecken, A. 1991 Potential taxonomic applications of H.P.L.C. analysis of Coccoidea pigments (Homoptera: Sternorhyncha).. Belgian Journal of Zoology 121(2): 211-225.

Notes: Abstract: High Performance Liquid Chromatography (HPLC) was applied to separate and identify the constituents of the pigments of scale insects; attempt to classify Kermes biblicus and K. palestiniensis; attempt to clarify relationship between K. vermilio and K. ballotae, living on the same plant species; search for complementary evidence for a suggested identity of Porphyrophora polonica and P. crithmi.