"An Analysis Of President Lincoln's Legal Arguments Against Secession" (1995).
For your further amusement, there was also this 1881 discussion of secession by a thoroughgoing Unionist apologist:
Cyclopædia of Political Science, Political Economy, and the Political History of the United States by the Best American and European Writers (1881), Published: New York: Maynard, Merrill, and Co., 1899. First published: 1881
Yeah.