Version 1 of Level 2 of SED-ML was published on December 2, 2013.
The specification can be found at:
Identifier for this specification is: https://identifiers.org/combine.specifications:sed-ml.level-1.version-2
To cite this document use:
Bergmann FT, Cooper J, Le Novère N, Nickerson D, Waltemath D. Simulation Experiment Description Markup Language (SED-ML) Level 1 Version 2. J Integr Bioinform. 2015 Sep 4;12(2):262. doi: 10.2390/biecoll-jib-2015-262. PMID: 26528560.
Frank T. Bergmann, Jonathan Cooper, Nicolas Le Novère, David Nickerson, Dagmar Waltemath. Simulation Experiment Description Markup Language (SED-ML): Level 1 Version 2. Available from COMBINE https://identifiers.org/combine.specifications:sed-ml.level-1.version-2 (2013)