Selstam, Gunnar, Jan Sondell, and Peter Olsson. 2015. “Wintering Area and Migration Routes for Ortolan Buntings Emberiza Hortulana from Sweden Determined With Light-Loggers”. Ornis Svecica 25 (1–2). Lund, Sweden:3–14. https://doi.org/10.34080/os.v25.19599.