Mr. F. G. Simpson, C.B.E.

f-DERIVATIONS AND (f; g)-DERIVATIONS OF MV -ALGEBRAS

Recently, the algebraic theory of MV -algebras is intensively studied. In this paper, we extend the concept of derivation of $MV$-algebras and we give someillustrative examples. Moreover, as a generalization of derivations of $MV$ -algebraswe introduce the notion of $f$-derivations and $(f; g)$-derivations of $MV$-algebras.Also, we investigate some properties of them.

Mr. R. G. Paul

was a graduate of Edinburgh University in 1927. He became a Fellow of the Royal College of Surgeons in Edinburgh, and was very proud when he was elected Fellow of the Royal College of Surgeons of England (ad eundem) in 1959. In addition, Mr. Paul became a Fellow of the Association of Surgeons of Great Britain, and a member of the council. He was a member and past president of the Moynihan Chiru...

Manuscript Manager™, CBE Style

"SMELL THE ROSES" (upper-case letters are the program's). The program thought I didn't smell the roses because I was leading too hectic a life. Although busy, I do nonetheless take time for such things, but I answered "No" to that question because of rather severe allergies! Nevertheless, as a patient who had just spent a considerable amount of time entering the data, I was pleased the program ...

(f) pinch (g)

F P M G

In group theory, it is a fundamental question to determine what information about a group is necessary and sufficient tomake a group finitely presented. In this paper, we develop the theory of Σ-invariants due to Robert Bieri and Ralph Strebel [Bieri] whi provides an answer to this question for the class of metabelian groups. We begin our study of Σ-invariants with a digression on group extens...