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Notwithstanding the provisions of the preceding Article, the judicial or administrative authority of the requested State is not bound to order the return of the child if the person, institution or other body which opposes its return establishes that -
a. the person, institution or other body having the care of the person of the child was not actually exercising the custody rights at the time of removal or retention, or had consented to or subsequently acquiesced in the removal or retention; or
b. there is a grave risk that his or her return would expose the child to physical or psychological harm or otherwise place the child in an intolerable situation.
The judicial or administrative authority may also refuse to order the return of the child if it finds that the child objects to being returned and has attained an age and degree of maturity at which it is appropriate to take account of its views.
In considering the circumstances referred to in this Article, the judicial and administrative authorities shall take into account the information relating to the social background of the child provided by the Central Authority or other competent authority of the child's habitual residence.