Val, Francisca C. do. “On the Biometyry and Evolution of the Genus Ornidia (Diptera, Syrphidae)”. Papéis Avulsos De Zoologia, vol. 26, no. 1-24 (1972-1973), Feb. 1972, pp. 1-28, https://doi.org/10.11606/0031-1049.1972.26.p1-28.