Casali, Maria Rita. "A combinatorial characterization of 4-dimensional handlebodies " Forum Mathematicum, 4.4 (2009): 123-134. Retrieved 19 May. 2013, from doi:10.1515/form.1992.4.123

Casali, M. (2009). A combinatorial characterization of 4-dimensional handlebodies . Forum Mathematicum, 4(4), pp. 1-633. Retrieved 19 May. 2013, from doi:10.1515/form.1992.4.123

Casali, Maria Rita. 2009. A combinatorial characterization of 4-dimensional handlebodies . Forum Mathematicum. 4(4): 1-633. Retrieved 19 May. 2013, from doi:10.1515/form.1992.4.123