1. Cranham, J. E.: Laboratory determination of resistance to tetradifbn in the fruit tree spider mite, Panonychus ulmi (Koch). Rep. E. Mailing Res. Sta. for 1967 pp. 165–168, 1968.
2. Foott, W. H. and Boyce, H. R.: A modification of the leaf-disc technique for acaricide tests. Proc. Entomol. Soc. Ont. (1965) pp. 117–119, 1966.
3. Harrison, R. A.: Topical application of insecticide solutions to mites and small insects. N.Z. J. Sci. 4: 534–539, 1961.
4. Heme, D.C.: A method for determining resistance in phytophagous mites. Pesticide Progress C.D. A. Research Report, Ottawa 7: 81–86, 1969.
5. Hoyt, S. C., Harries, F. H.r Laboratory and field studies on orchard-mite resistance to Kelthane. J. Econ. Entomol. 54 (1): 12–16, 1961.