Pure Theory of Law

Reprint of the second revised and enlarged edition, being a completely revised
version of the first edition which was published in 1934. Kelsen
[1881-1973], was the author of more than forty works on law and legal
philosophy, and is best known for this title and General Theory of Law
and State. He was also the author of the Austrian Democratic
Constitution, which was published in 1920, abolished during the Nazi
regime, restored in 1945, and in force today. Walker calls Kelsen
"possibly the most influential jurisprudent of the twentieth century."
Walker, Oxford Companion to Law 699.