1. ISO , International Standard ISO 30500: Non-sewered sanitation systems - Prefabricated integrated treatment units - general safety and performance requirements for design and testing , ISO , 2018
2. United Nations (UN) , Transforming our World: the 2030 Agenda for Sustainable Development , UN General Assembly , 2015
3. L. Strande , M.Ronteltap and D.Brdjanovic , Faecal Sludge Management – Systems Approach for Implementation and Operation , IWA Publishing , 2014
4. Do septic tank systems pose a hidden threat to water quality?
5. United Nations Children's Fund (UNICEF) and World Health Organization (WHO) , Progress on household drinking water, sanitation and hygiene 2000–2017, Special Focus on Inequalities , New York , 2019