N.Y.C. Admin. Code § 19-132: § 19-132 Restrictions on First place, Second place, Third place and Fourth place in the borough of Brooklyn.

The buildings to be erected upon the lots fronting upon first place, second place, third place and fourth place in the borough of Brooklyn, shall be built on a line thirty-three feet five inches and a quarter of an inch back from the sides or lines of such places as they are now established by the map of the city, and the intervening space of land shall be used for courtyards only.