WHO. (1996). Obstructed labour module. education material for teachers of midwifery. WHO.
Chicago-viite (17. p.)WHO. Obstructed Labour Module. Education Material for Teachers of Midwifery. WHO, 1996.
MLA-viite (9. p.)WHO. Obstructed Labour Module. Education Material for Teachers of Midwifery. WHO, 1996.
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