Major J. B. Corkern and Mrs. J. B. Corkern are listed as having died of yellow fever in Vicksburg, Mississippi in 1878 on page 243 of the book, "A History of Yellow Fever" by John McLeod Keating published in 1879.

Below are 2 different links for viewing online:

http://www.archive.org/details/ahistoryyellowf00keatgoog

http://books.google.com/books?id=ZQMW-S0MRjkC&pg=PA243&lpg=PA243&dq=james+b.+corkern&source=bl&ots=jARNoWrm_1&sig=tQdWirap5LtddBpNKqS_TUBZSSM&hl=en&ei=W0KiTc7GJYH10gGOh-jlDg&sa=X&oi=book_result&ct=result&resnum=2&ved=0CBYQ6AEwATgK#v=onepage&q=james%20b.%20corkern&f=false

Could this be the same couple?

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