[Proj] proj4 string for perfect sphere

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> "Fischer, Robert P. (GISS-6110)[COLUMBIA UNIVERSITY]" [robert.p.fischer-1 at nasa.gov] kirjoitti: 
> > Although the theory for all this is probably sitting in a geometry book somewhere..
> 
> I find this web site very informative for a beginner:
> 
> http://aa.quae.nl/en/index.html
> 
> this shows all the most basic calculations with examples
> 
> regards: Janne.
> 

still better link might be 

http://aa.quae.nl/en/reken/grootcirkel.html#1

regards: Janne.