Reference

Petr Heneberg, Jiri Sirek, Vlasta Skorpikova, Karel Simecek, Jiri Safranek, Daniel Mazanek, Zdenek Hubalek, Eva Jerabkova (2006): Overview of sand martin (Riparia riparia) localities in the Czech Republic – Linzer biologische Beiträge – 0038_2: 1413 - 1447.