In addition to providing information for general use, it documents local variations such as U.S. and U.K. usage.
They are based on the research by Dartmouth experts who have documented wide geographic variations in health spending.
It was for this reason that Joseph Karo's Shulchan Aruch did not become established as the authoritative code of Jewish law until after Moshe Isserlis added his commentary, which documented variations in local custom.
The leading historians of the period, Michael Vickery ("Cambodia 1975-1982") and Ben Kiernan ("How Pol Pot Came to Power"), have both documented, for example, the gradations and variations in hardship and terror from one region or district to another.
A few books have documented different variations of this simple, anonymously written diet plan, which surprisingly has survived the test of time.
With an ambitious, two-part survey, "Photographing Maine: 1840-2000," the Maine Coast Artists/Center for Maine Contemporary Art documents the themes and variations of photographers' rich and complex reactions to this landscape and its inhabitants.
Yet multiple researchers have documented variations in bleaching susceptibility that may be termed 'experience-mediated tolerance'.
She documented regional variations of traditional costumes, the bunad, and was a pioneer in bringing the bunad into a wider public.