You may also wish to search for items by Deelstra, B. and Deelstra.
Only one matching reference was found.
Karasek, F.W.; Grimard, A.I.; Deelstra, B.L., Quantitative analysis of chloro-fluorobenzenes by gas chromatography, J. Chromatogr. Sci., 1972, 10, 12, 725-726, https://doi.org/10.1093/chromsci/10.12.725 . [all data]