figures of the EWAS95 article 
 ( images and animations are copyrighted: no public use
				 is allowed without author autorization. )
  
  
  
 
  
  
(mpeg animations can be seen on my research page). 
(the flag model is due to Xavier Provot).
 ( images and animations are copyrighted: no public use
				 is allowed without author autorization. )