Jean,

Here's my translation of the reference:

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Burkhart, Josef, occupation shoemaker, a Rifleman ("Musketier") with the 476th Wurtt. Infantry Regiment, born on November 15, 1885 in Wurmlingen, son of (the late) Jakob Burkhart and Elisabethe (nee Liebermann), a resident of Wurmlingen, died of wounds received to the head, chest and right lower leg ("Unterschenkel") in the "Theaterlazarett" [some sort of hospital, possibly just a casualty clearing station] Montmedy on September 8, 1917.
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Also, from Heilbronn:

Burkert, Friedrich *19. 9. 1898 in London
Burkert, Jakob *29. 9. 1890 in Heilbronn
Burkhardt, Karl *19. 6. 1889 in Kirchheim u. T.
Burkhardt, Karl *18. 8. 1893 in Heilbronn
Burkhardt, Richard *20. 11. 1892 in Heilbronn

I can provide a translation of the full entry for any of these if you would like one.

Ken
http://ca.geocities.com/scheffkg.rm/gen.html