P. A. Borges, A. S. Rodrigues, S. E. Silva, S. G. Seabra, O. S. Paulo, and J. A. Quartau, “New data on polymorphism of the meadow spittlebug Philaenus spumarius (L.) (Hemiptera: Aphrophoridae) from the island of São Miguel (Azores)”, Zootaxa, vol. 4369, no. 1, pp. 144–150, Jan. 2018.