RISBERG, Birger. Density and diversity of breeding birds in forests in the province of Ångermanland. Ornis Svecica, Lund, Sweden, v. 7, n. 3–4, p. 97–106, 1997. DOI: 10.34080/os.v7.22963. Disponível em: https://journals.lub.lu.se/os/article/view/22963. Acesso em: 5 may. 2024.