Submitted on: 27 February 2007.
Revised on: 18 April 2007.
Accepted on: 31 May 2007.
___________________Child Indicators Research---SPRINGER
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Submitted on: 24 August 2016.
Revised on: 04 December 2016.
Accepted on: 27 January 2017.
___________________Child Indicators Research---SPRINGER
Submitted on: 06 February 2025.
Revised on: 06 May 2025.
Accepted on: 04 June 2025.
___________________Child Indicators Research---SPRINGER
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