Källander, H. Flock-Fishing Deep-Diving Piscivores (Great Crested Grebe Podiceps Cristatus, Great Cormorant Phalacrocorax Carbo, Common Merganser Mergus Merganser) at Lake Vombsjön, Southern Sweden, and Those That Exploit Them. Ornis Svec 2018, 28, 14–18.