Columbia subject headings:
Harvard subject headings:
North Frisian Islands (Denmark and Germany)--History--18th century.
Petersen, Ipke--Correspondence.
Petersen, Ipke.
Seafaring life--North Frisian Islands (Denmark and Germany)--History--18th century.
Ship captains' spouses--North Frisian Islands (Denmark and Germany)--Correspondence.
Ship captains--North Frisian Islands (Denmark and Germany)--Biography.
Ship captains--North Frisian Islands (Denmark and Germany)--Correspondence.
Princeton subject headings:
North Frisian Islands (Denmark and Germany)--History--18th century.
Petersen, Ipke--Correspondence.
Petersen, Ipke.
Seafaring life--North Frisian Islands (Denmark and Germany)--History--18th century.
Ship captains' spouses--North Frisian Islands (Denmark and Germany)--Correspondence.
Ship captains--North Frisian Islands (Denmark and Germany)--Biography.
Ship captains--North Frisian Islands (Denmark and Germany)--Correspondence.