title: Qat chewing and water pipe (mada'a) smoking in Yemen: a necessary clarification when studying health effects on oral mucosa.
authors.forename: Kamal T
authors.initials: KT
authors.lastname: Chaouachi
mesh_terms: D029754:Catha / Q000009:adverse effects*; D006801:Humans; D009061:Mouth Mucosa / Q000187:drug effects*; D012907:Smoking / Q000009:adverse effects*; D015006:Yemen