APA
WHO, . (1998). Cancer pain relief and palliative care in children. auth., Geneva: .
Chicago
WHO, . 1998. Cancer pain relief and palliative care in children. auth., Geneva: .
Harvard
WHO, . (1998). Cancer pain relief and palliative care in children. auth., Geneva: .
MLA
WHO, . Cancer pain relief and palliative care in children. auth., Geneva: . 1998.