Like his father, Roman maintained an extensive correspondence with relatives in Poland. Following a visit to Poland in 1932, Roman wrote both to Polish friends and to young American acquaintances who had traveled with him. Roman continued the family correspondence with the Jaclowska family in Warsaw, who were related to his Dyniewicz relatives, and with several individuals in the Jaroslaw region from which his father had come. Despite the changes in the European political situation during the 1930's, there is little comment in these letters other than on matters of personal interest. Other letters written and received by Roman concern his takeover of his father's role as agricultural editor of the Kuryer Polski following his father's death.
Later correspondence deals mainly with the family genealogy.
The results of Roman Kwasniewski's researches into the family history are contained in a separate folder, and include a handwritten family tree, his handwritten reminiscences of his grandparents and relatives, obituaries and newspaper clippings concerning Jozef Kwasniewski and Wladyslaw Dyniewicz, and other papers. Business records in the collection are numerous, and include Art Flower Shop client records, with correspondence, orders, and occasionally, samples of products ordered or offered for sale. Most of these records date from 1949 to 1952, when Roman Kwasniewski ran the business. Among the customers were retailers, and wholesale firms and suppliers. Together, these records provide an interesting view of a small Milwaukee business.