Unfortunately I too can not gain access to the original article as they are asking for payment. They also do not have the DOI of this article (I would have accessed this by that method). However, the reference is as follows;
The journal of laboratory and clinical medicines, March 1953 Volume 41, Issue 3, Pages 486–492
You may find the original method in some text books like, Techniques in Biochemistry by Sadashivam, or Plummer, or Harper (techniques in medical biochemistry).