Procedure for finding a minimal element, in a relation R in A

   procedure Min(a)		- input: an arbitrary element a of A
				- output: m is a minimal element of R
1) m <- a; 
2) j=0
3) if there is no element x such that x R m
4)    then return
5)    else take an element x such that x R m
6)	   m <- x
7) j <- j+1
8) go to (3)

Algorithm for finding a total order R', given by a numbering a'[i],
such that R is a subset of R'

1) i=1
2) take an arbitrary unmarked element a of A
3) Min[a]
4) a'[i] <- m
5) mark m
6) if i=|A| then stop
7)	    else i <- i+1; go to (2)