Update README.md

README.md

@@ -5,8 +5,8 @@ PyBetVH is an open and cross-platform implementation of BET_VH model. The main p
 More datails on the PyBetVH software can be found in Tonini et al. (2015). A general user guide for all PyBet tools can be found at https://vhub.org/wiki/PyBetToolsUserGuide.
 
 **References:** 
- - *Marzocchi W., Sandri L., Selva J. (2010) BETVH: a probabilistic tool for long-term volcanic hazard assessment, Bull. Volcanol., 72, 705-716, DOI:10.1007/s00445-010-0357-8* 
- - *Tonini R., Sandri L., Thompson M. A. (2015) PyBetVH: a Python tool for probabilistic volcanic hazard assessment and for generation of Bayesian hazard curves and maps, Comput. Geosci., doi:10.1016/j.cageo.2015.02.017*
+ - *Marzocchi W., Sandri L., Selva J. (2010) BETVH: a probabilistic tool for long-term volcanic hazard assessment, Bull. Volcanol., 72, 705-716, [doi:10.1007/s00445-010-0357-8(https://link.springer.com/article/10.1007%2Fs00445-010-0357-8)* 
+ - *Tonini R., Sandri L., Thompson M. A. (2015) PyBetVH: a Python tool for probabilistic volcanic hazard assessment and for generation of Bayesian hazard curves and maps, Comput. Geosci., [doi:10.1016/j.cageo.2015.02.017](https://www.sciencedirect.com/science/article/pii/S0098300415000515)*
 
 
 ## Requirements