I can't fidn the picture of it now, but i think it had horizontal stripes that from top to bottom were; purple yellow then green or red and in the middle of the yellow strip was a red coloured thing that I think was like three lines that met in the middle at 120* from each other . . .
I'm good at geography and flags in particular cos I have quite a good photographic memory, so if I see one I don't recognise it annoys me if i can't work it out . . .
Seems theres only spain , nicaragua and dominica are national flas with purple in them.
http://www.itwaslost..../03/purple-flags.html
Seems the flag of the brigades was a flag that people fighting against Franco , fought under.