Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:Several laparoscopic techniques have been described as alternatives for the endoscopic treatment of ovarian endometriomas: cyst wall laser vaporization preceded or not by medical therapy (Brosens et al., 1996; Donnez et al., 1996; Sutton et al., 1997), drainage and bipolar coagulation of the cyst wall (Beretta et al.
Category: