Robert de Vaugondy and son were related to the Sanson family and had inherited many of their plates which they used as a basis for their Atlas Universel which C. F. Delamarche later took over.  It was probably Delamarche who changed Iceland on this Vaugondy-map from the Sanson-type to Knoff. The year 1756 on one copy refers to the older version (see map with same title).
Iceland is part of a large map of Scandinavia.