Elts, J., Kuresoo, A., Leibak, E., Leito, A., Leivits, A., Lilleleht, V., Luigujõe, L., Mägi, E. et al. 2009.
Status and numbers of Estonian birds, 2003–2008. Hirundo 22, 3-32. (in Estonian with English summary)
Luigujõe, L. 2011. Midwinter waterfowl in Estonia. Eesti Loodus, 4, 24-29. (in Estonian)
Since 1995 the project is included in the Estonian national program of biological monitoring and financed by the state (currently by the Estonian Environmental Board). The budget in recent years has been ca 3800 EUR but the real cost would be ca 6000 EUR).