The owners of the bookshop were diligent in collecting various documents related to the activities of the bookshop. Several bills prepared by Marija Šlapelienė for the sale of books and periodicals in different periods of the bookshop
Pranas Bieliauskas was an important figure in the Lithuanian society of the Vilnius region, one of the founders of the Lithuanian Society for Aid to War Victims. The invoice reveals that he visited and bought books from Marija Šlapelienė's bookshop