A limit on the intensity of use of a piece of land where the percentage of the lot area that may be occupied by a structure is set at a maximum level by law is an example of what regulation?

How would you cite different books by the same author on the works cited page? a. moore, jack h. folk songs and ballads. salem: poetry press, 1999. print. moore, jack h. ballads in poetry – a critical review. dallas: garden books, 1962. print. b. moore, jack h. folk songs and ballads. salem: poetry press, 1999. print. –––. ballads in poetry – a critical review. dallas: garden books, 1962. print. c. moore, jack h. ballads in poetry – a critical review. dallas: garden books, 1962. print. moore, jack h. folk songs and ballads. salem: poetry press, 1999. print. d. moore, jack h. ballads in poetry – a critical review. dallas: garden books, 1962. print. –––. folk songs and ballads. salem: poetry press, 1999. print.