The main goal of the work is to study some basic properties of free groups, by using group
theory and topology. For this, graphs play a main role, since we will prove that the …

O objetivo desse trabalho é estudar a Conjectura de Hanna Neumann, que surgiu a partir
do conhecido resultado provado por Howson e fornece um limitante para o posto da …

In 1966, F. Rhodes introduced the idea of the fundamental group of a group G of
homeomorphisms of a topological space X. His article contains summarized proofs of …