Majda Cohodar Wolfgang Borutzky Vjekoslav Damic Comparison of different formulations of 2D beam elements based on Bond Graph technique. 107-124 2009 17 Simulation Modelling Practice and Theory 1 http://dx.doi.org/10.1016/j.simpat.2008.02.014 db/journals/simpra/simpra17.html#CohodarBD09