1. Andrzejewska, L. (1971): Productivity investigation on two types of meadows in the Vistula valley. VI. Production and population density of leafhopper (Homoptera-Auchenorrhyncha) communities. Ekol. pol. 19: 151–172.
2. (1976): The influence of mineral fertilization of the meadow phytophagous fauna. Pol. ecol. Stud. 2: 93–109.
3. (1979 a): Herbivorous fauna and its role in the economy of grassland ecosystems. I. Herbivores in natural and managed meadows. Pol. ecol. Stud. 5: 5–44.
4. (1979 b): Herbivorous fauna and its role in the economy of grassland ecosystems. II. The role of herbivores in trophic relationships. Pol. ecol. Stud. 5: 45–76.
5. Baker, C. J. (1946): A note on the estimation of the uric acid radical in avian excreta. Poultry Sci. 25: 593–604.