La Vanguardia newspaper, in an article by Teresa María Amiguet, remembers the exection of 13 young women reviled as “communists” by the Franco regime on August 5, 1939. These events led to the novel Las Trece Rosas [The Thirteen Roses, 2003] by Jesús Ferrero, and the study Trece Rosas Rojas [Thirteen Red Roses, 2004] by the journalist Carlos Fonseca. The basics are summarized in the Wikipedia article. A more exhaustive study on Ferrero’s and Fonseca’s treatment of the historical facts by Kasja Larson (in English) was published in Nomenclatura (U of Kentucky, 2012). A similar study by Jaime Céspedes (in Spanish) was already published in 2007 in Tonos (Revista Electrónica de Estudios Filológicos).