▁ 1 9 8 6 . ▁Lars ▁Vin x , ▁Hans ▁K elsen ' s ▁P ure ▁Theory ▁of ▁Law , ▁Oxford ▁ 2 0 0 7 . ▁ ▁External ▁links ▁▁ ▁' The ▁P ure ▁Theory ▁of ▁Law ', ▁Stan ford ▁Encyclopedia ▁of ▁Philosoph y . ▁ ▁Category : 1 9 3 4 ▁non - f iction ▁books ▁Category : Book s ▁about ▁juris pr ud ence <0x0A> </s> ▁David ▁Hall iday ▁M off at ▁( J uly ▁ 2 2 , ▁ 1 8 3 9 ▁– ▁March ▁ 1 8 , ▁ 1 9 1 1 ) ▁was ▁an ▁American ▁financi er ▁and ▁industrial ist . ▁ ▁M off at ▁was ▁one ▁of ▁Den ver ' s ▁most ▁important ▁financi ers ▁and ▁industrial ists ▁in ▁late ▁ 1 9 th ▁and ▁early ▁ 2 0 th ▁century ▁Colorado , ▁and ▁he ▁was ▁responsible ▁for ▁the ▁development ▁of ▁the ▁Middle ▁Park ▁area . ▁He ▁served ▁as ▁president , ▁tre as urer ▁and ▁as ▁a ▁board ▁member ▁of ▁rail ro ads , ▁banks ▁and ▁city ▁government ▁posts . ▁Over ▁the ▁years ▁he ▁had ▁claims ▁to ▁over ▁one ▁hundred ▁Colorado ▁mines ▁and ▁nine ▁rail ro ads . ▁M off at ▁died ▁on ▁March ▁ 1 8 , ▁ 1 9 1 1 ▁in ▁New ▁York ▁City ▁at ▁the ▁age ▁of ▁sevent y ▁three . ▁Some ▁had ▁said ▁that ▁he ▁had ▁vain ly ▁spent ▁four teen ▁million ▁dollars ▁on ▁the ▁dream ▁of ▁a ▁rail road ▁directly ▁west ▁from ▁Den ver . ▁The ▁Den ver