Superplasticity in silicon nitride through the $\mathsf{\alpha}$ to $\mathsf{\beta}$ phase transformation Fabrice Rossignol, Tanguy Roussel, Jean-Louis Besson, Paul Goursat et Pierre Lespade J. Phys. III France, 5 2 (1995) 127-134 DOI: 10.1051/jp3:1995114