de Ong, E.R., Knight, H., & Chamberlin, J.C. 1927 A preliminary study of petroleum oil as an insecticde for citrus trees.. Hilgardia 2(9): 351-384.

Notes: Mealybugs were among the pests species treated with chemical controls. Species mentioned include Chrysomphalus aurantii, Phenacoccus colemani and Saissetia oleae.