1 literature reference for Aprostocetus vacuna (Walker, 1839):

Author: Graham, M.W.R. de V.
Year: 1961
Title: The genus |Aprostocetus| Westwood sensu lato (Hym., Eulophidae) notes on the synonymy of European species.
Source: JOURBOOK: Entomologist's Monthly Magazine VOLUME: 97 PAGES: 34-64