A Common Epineural Sheath for the Nerves in the Popliteal Fossa and Its Possible Implications for Sciatic Nerve Block. - Vloka,J.D.; Hadzic,A.; Lesser,J.B.; Kitain,E.; Geatz,H.; April,E.W.; Thys,D.M. (Anesth Analg, 1997)