The first extant Breton texts, contained in the Leyde manuscript, were written at the end of the 8th century: 50 years prior to the Strasbourg Oaths, considered to be the earliest example of French. Like many medieval orthographies, Old- and Middle Breton orthography was at first not standardised, and the spelling of a particular word varied at authors' discretion. In 1499, however, the "Catholicon", was published; as the first dictionary written for both French and Breton, it became a point of reference on how to transcribe the language. The orthography presented in the "Catholicon" was largely similar to that of French, in particular with respect to the representation of vowels, as well as the use of both the Latinate digraph —a remnant of the sound change /kʷ/ > /k/ in Latin—and Brittonic or to represent /k/ before front vowels.