1. Blok, I., A.H. Eenink, 1974. Bremia in latucae sorten, in het bijzonder in L. sativa. Zaadbelangen 28: 138–40.
2. Blok, I., J.J.M. Van Bakel, 1976. Wit in sla. Groenten en Fruit, No. 31638, 172.
3. Blok, I., Van Der Schaf-Van Waadenooyen Kernekamp, 1977. Problemen rond Bremia in sla. Zaadbelangen 31: 5758, 60.
4. Crute, I.R., 1987. The occurrence, characteristics, distribution, genetics and control of a metalaxyl-resistant pathotype of Bremia lactucae in the United Kingdom. Plant Disease 71: 763–767.
5. Crute, I.R., 1989. Lettuce downy mildew: a case study in integrated control. In: K.J. Leonard, W.E. Fry (Eds.) Plant Disease Epidemiology Vol. 2, pp. 30–53. McGraw-Hill, New York.