Submitted on: 01 April 2008.
Revised on: 21 April 2008.
Accepted on: 13 May 2008.
NULL
Submitted on: 01 October 2006.
Revised on: 15 October 2006.
Accepted on: 26 October 2006.
NULL
Submitted on: 07 February 2004.
Revised on: 06 March 2004.
Accepted on: 03 April 2004.
TechTrends---SPRINGER INT PUBL AG
Submitted on: 18 July 2018.
Revised on: 14 August 2018.
Accepted on: 02 September 2018.
NULL
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Submitted on: 14 April 2009.
Revised on: 19 May 2009.
Accepted on: 14 June 2009.
TechTrends---SPRINGER INT PUBL AG
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