1. Ambulatory surgery in the United States, 2006;KA Cullen;Natl Health Stat Report,2009
2. Hospital Episode Statistics (2015) Admitted Patient Care—England, 2014–15: Main Operations, 4 Character Table. Health and Social Care Information Centre. Secondary Hospital Episode Statistics, Admitted Patient Care—England, 2014–15: Main Operations, 4 Character Table. Health and Social Care Information Centre. http://www.hscic.gov.uk/article/2021/Website-Search?productid=19420&q=Hospital+Episode+Statistics%2c+Admitted+Patient+Care&sort=Relevance&size=10&page=1&area=both#top.
3. Statistisches Bundesamt. Gesundheit (2014). Fallpauschalenbezogene Krankenhausstatistik (DRG-Statistik) 2014. Secondary Statistisches Bundesamt. Gesundheit. Fallpauschalenbezogene Krankenhausstatistik (DRG-Statistik) 2014. https://www.destatis.de/DE/Publikationen/Thematisch/Gesundheit/Krankenhaeuser/FallpauschalenKrankenhaus2120640147004.pdf?__blob=publicationFile.
4. Swedish guidelines for the treatment of pain in tonsil surgery in pediatric patients up to 18 years;E Ericsson;Int J Pediatr Otorhinolaryngol,2015
5. Pain Intensity on the First Day after Surgery: A Prospective Cohort Study Comparing 179 Surgical Procedures;HJ Gerbershagen;Anesthesiology,2013