There is a free pattern at the moda web site called Urban Cowgirl, maybe it is what you are looking for.

I found Aunt Martha's Rose in Maggie Malone's 1001 Patchwork Designs, last reprinted 1982; hope this helps. Maggies books were some of the first I collected 30 years ago - she doesn't give instructions so her books are just like a dictionary of pictures[ATTACH=CONFIG]524809[/ATTACH]

Here is Martha Washington Star, also by Maggie Malone. Not being American, I don't know the relationship between Aunt Martha and Martha Washington! [ATTACH=CONFIG]525186[/ATTACH]