The sole source of this marriage derives from a handwritten diary by Philippe Le Couteur (1826-1903) who emigrated to Australia, and would have been one of his g-g-g grandmothers..
No archived documentation has been found to corroborate it, BUT there are archives that show Elizabeth Bechervaise, at the same g-g-g-grandmother generation, on another branch of his ancestors: Philippe<Thomas<Thomas<Elizabeth Asplet<Francois Mauger<Elizabeth Bechervaise.
Family ancestral information in the diary prior to ~1760 is very scant, and it is concluded that 100 years of word-of-mouth tradition and memory confused the facts for this ancestor. Thus Elizabeth Bechervaise (1685-1750), who was daughter of Guilleaume, is not thought to have been the wife of Mathieu Le Couteur (1685-1710) and Philippe's memory over 5 generations confused the ancestral branch. Philippe's known ancestor Elizabeth Bechervaise, baptised in 1699, who married Elie Mauger is shown on the family tree.