Well rewrite orderings

A study is made of well (quasi) orderings which are described as rewrite orderings, and a family of well (quasi) orderings that extends the embedding or divisibility order of G. Higman (1952) is presented. For instance, the well (quasi) orderings proposed by the author may contain pairs of the form f(f(x))>f(g(f(x))). Conditions under which the transitive closures of a well-founded relation is a well-quasi-ordering are given. Finally, an attempt to extend the recursive path ordering is proposed.<<ETX>>