APA
Sommer A., . (1978). Field guide to the detection and control of xerophthalmia. WHO, Geneva: .
Chicago
Sommer Alfred, . 1978. Field guide to the detection and control of xerophthalmia. WHO, Geneva: .
Harvard
Sommer A., . (1978). Field guide to the detection and control of xerophthalmia. WHO, Geneva: .
MLA
Sommer Alfred, . Field guide to the detection and control of xerophthalmia. WHO, Geneva: . 1978.