What does “Vertex Solution” mean?

Hello!

I come across the word "vertex solution" in the context " We can also assume that x and y are vertex solutions,so that the sequence {x,y} remains in a finite set."

Could anybody know any definition for "Vertex Solution"?

Thanks,

Tendow

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A bit more context would help. –  Federico Poloni May 20 '13 at 8:42
A citation of the paper or book in which you found this phrase, for example. –  Lee Mosher May 20 '13 at 13:09
Thanks. It is a proof of convergence to critical point in Gauss-Seidel Method. The phrase appears in "Grippo, L., and M. Sciandrone. "On the convergence of the block nonlinear Gauss–Seidel method under convex constraints." Operations Research Letters 26.3 (2000): 127-136." –  tendow May 22 '13 at 3:02