Kalinski, A., M. Markowski, M. Banbura, W. Mikus, J. Skwarska, J. Wawrzyniak, M. Gladalski, P. Zielinski, and J. Banbura. “Weak Correlation Between Haemoglobin Concentration and Haematocrit of Nestling Great Tits Parus Major and Blue Tits P. Caeruleus”. Ornis Fennica, vol. 88, no. 4, Dec. 2011, pp. 234–240, doi:10.51812/of.133787.