société (humaine) (2) recherche (2) participation (2) musique (2) métal (2) hôpital (2) métal lourd (2) ethnologie (2) alcool (2) éducation (2) âge (2) Education (2) Adversaries (2) Music (2) Music (2) Scores (2) Enemies (2) Music fans (2) Musicals--Librettos (2) Young adults (2) Weights and measures (2) Tallies (2) Symptoms (2) Suicide (2) Songs--Texts (2) Social problems (2) Satanism (2) Research (2) Psychology, Pathological (2) Population (2)