P. H. E. D. Bhutan. Pu BT,
« Additional technical details in the Handbook on toilets in Bhutan », in
Handbook on toilet options for rural households in Bhutan : rural sanitation and hygiene programme, Thimphu, Bhutan: Bhutan, Ministry of Health, Public Health Department, PHED, 2012, p. 5 p. (43-47); tab.; fig.