The Seventeenth Century Dutch practice of dropping the last name caused authors problems

Both Dr. Carl Ballhausen and C. T. Atkinson, the editor of the latter editions of The First Dutch War, were both affected by the Seventeenth Century Dutch practice of omitting a captain's last name. The example which arose today, was that of Allert Janszoon and Allert Janszoon Tamessen. Allert Janszoon, in 1652, was in the service of the Vlissingen Directors, while Allert Janszoon Tamessen was in the service of the Admiralty of the Noorderkwartier. Allert Janszoon was with Tromp's fleet in May 1652, and was sent into the Downs with Isaak De Jongh to request the return of Bastiaan Tuyneman's ship, the Sint Laurens. The Sint Laurens had been taken by the English on 29 May 1652, in the fight between the English and Dutch fleets under Blake and Tromp, in the seas off Dover. We don't know the name of the Zeeland captain, Allert Janszoon, although we know that later, he commanded the Zeeland ship Dubbele Arend (28 guns). Allert Janszoon Tamessen commanded the Wapen van Hoorn (or Eenhoorn), a vessel of 30 guns and a crew of 115 men. In late March or early April 1653, Allert Jansz. Tamessen's ship was lying in the roads off Hoorn. His ship was one of the 100 ships of the "extraordinary equipage" hired in 1652, while Allert Janszoon's was one of the 50 Directors' ships hired in 1652.