Swimming at the 2010 Summer Youth Olympics – Mixed 4 x 100 metre medley relay
The mixed 4 × 100 metre medley relay event at the 2010 Youth Olympic Games took place on August 20, at the Singapore Sports School.
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Wikipedia
The mixed 4 × 100 metre medley relay event at the 2010 Youth Olympic Games took place on August 20, at the Singapore Sports School.