A note on free groups

@inproceedings{Burns1969ANO,
  title={A note on free groups},
  author={Robert G. Burns},
  year={1969}
}
The object of this note is to point out a theorem of M. Hall, Jr. (Theorem 1), proved, but formulated in a weaker form, as Theorem 5.1 of [2]. We then show that results of Karrass and Solitar [5], and Howson [4], follow as relatively easy corollaries of this stronger statement (Corollaries 2 and 3). Since the terminology is not fixed, we note for definiteness that by a right transversal for a subgroup H in a group G we shall mean a complete set of representatives of cosets Hg, gEFG. Other terms… 
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