Díez Garretas, B. and Salvo Tierra, A. E. (1979) “On the existence of Polypodium macaronesicum Bobrov in the South of the Iberian Peninsula”, Acta Botanica Malacitana, 5, pp. 5–14. doi: 10.24310/Actabotanicaabmabm.v5i.9666.