Click Fibonacci_and_the_Financial_Revolution.pdf link to view the file.
This is a paper by the historian William H. Goetzmann (July 20, 1930 – September 7, 2010) , who in a Pulitzer Prize-winning book overturned the idea of Western exploration in the 19th century as a series of random thrusts into the hinterland, finding instead that it was a far more systematic effort.

William Henry Goetzmann was born on July 20, 1930, in Washington, and grew up in St. Paul and Houston. At Yale, where he earned a bachelor’s degree in 1952 and a doctorate in 1957 and taught from 1955 to 1964, his interest in the history of the West was sparked by the historian Howard R. Lamar. His dissertation was published in 1959 under the title “Army Exploration in the American West, 1803-1863.” (Excerpted from his obituary)

I came across this reference in Niall Ferguson's best seller, `The Ascent of Money' (Penguin, 2009), where he mentions it in a footnote (no 22, on page 32).