@book{ig00218600, author = {Gerson, Johannes}, title = {De custodia linguae et corde bene ruminanda}, year = {not after Sept. 1470]}, note = {}, publisher = {Peter Schoeffer}, address = {[Mainz}, annote = { This record was exported from the Incunabula Short Title Catalogue (ISTC): http://data.cerl.org/istc/ig00218600} }