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Submitted on: 28 June 2019.
Revised on: 07 August 2019.
Accepted on: 17 September 2019.
___________________Informatics in Education---VILNIUS UNIV, INST MATHEMATICS & INFORMATICS
Submitted on: 24 October 2004.
Revised on: 20 February 2005.
Accepted on: 19 March 2005.
___________________Informatics in Education---VILNIUS UNIV, INST MATHEMATICS & INFORMATICS
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Submitted on: 24 October 2010.
Revised on: 04 February 2011.
Accepted on: 19 March 2011.
___________________Informatics in Education---VILNIUS UNIV, INST MATHEMATICS & INFORMATICS
Submitted on: 13 March 2020.
Revised on: 16 May 2020.
Accepted on: 02 June 2020.
___________________Informatics in Education---VILNIUS UNIV, INST MATHEMATICS & INFORMATICS
Submitted on: 19 July 2022.
Revised on: 03 October 2022.
Accepted on: 25 October 2022.
___________________Informatics in Education---VILNIUS UNIV, INST MATHEMATICS & INFORMATICS
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Submitted on: 25 February 1999.
Revised on: 28 April 1999.
Accepted on: 22 June 1999.
___________________Informatics in Education---VILNIUS UNIV, INST MATHEMATICS & INFORMATICS