+@techreport{lambdadeltaR3a,
+ author="Ferruccio {Guidi}",
+ title="{The Formal System $\lambda\Upsilon\mathrm{P}$}",
+ type="Technical Report",
+ number="AMS Acta 5754",
+ institution="University of Bologna",
+ address="Bologna, Italy",
+ year="2018",
+ month="January"
+}
+
+@article{lambdadeltaJ3a,
+ author="Ferruccio {Guidi}",
+ title="{Verified Representations of Landau's ``Grundlagen'' in the $\lambda\delta$ Family and in the Calculus of Constructions}",
+ Publisher="University of Bologna",
+ address="Bologna, Italy",
+ journal="Journal of Formalized Reasoning",
+ volume="8",
+ number="1",
+ year="2015",
+ month="December",
+ pages="93--116"
+}
+
+% \lambda\delta version 2 (active) %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+@comment{lambdadeltaJ2a,
+ author="Ferruccio {Guidi}",
+ title="{The Formal System $\lambda\delta$ Revised: Extending the Applicability Condition}",
+ howpublished="CoRR identifier 1411.0154",
+ year="2014",
+ month="November",
+ note="Preprint (available at $<$\url{http://lambdadelta.info/}$>$)"
+}
+
+@techreport{lambdadeltaR2c,
+ author="Ferruccio {Guidi}",
+ title="{Extending the Applicability Condition in the Formal System $\lambda\delta$}",
+ type="Technical Report",
+ number="AMS Acta 4411",
+ institution="University of Bologna",
+ address="Bologna, Italy",
+ year="2015",
+ month="December"
+}
+
+@misc{lambdadeltaV2a,
+ author="Ferruccio {Guidi}",
+ title="{lambdadelta\_2A1}",