Submitted on: 01 March 2015.
Revised on: 30 April 2015.
Accepted on: 13 June 2015.
___________________BRITTONIA---SPRINGER
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Submitted on: 20 February 2002.
Revised on: 13 March 2002.
Accepted on: 28 April 2002.
___________________BRITTONIA---SPRINGER
Submitted on: 31 August 2006.
Revised on: 19 December 2006.
Accepted on: 21 January 2007.
___________________BRITTONIA---SPRINGER
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