Hake, Mikael, Donald Blomqvist, Elin P Pierce, Tommy Järås, and Olof C Johansson. 1998. “Population Size, Migration Routes and Breeding Origin of Purple Sandpipers Calidris Maritima Wintering in Sweden”. Ornis Svecica 8 (1–2). Lund, Sweden:64. https://doi.org/10.34080/os.v8.23125.