1. Billiet, C., Pons Frias, J.E., Pons, O., De Tré, G.: Bipolarity in the Querying of Temporal Databases. In: Atanassov, K.T., Homenda, W., Hryniewicz, O., Kacprzyk, J., Krawczak, M., Nahorski, Z., Szmidt, E., Zadrozny, S. (eds.) New trends in fuzzy sets, intuitionistic fuzzy sets, generalized nets and related topics volume II: applications, New trends edn., pp. 21–37. SRI PAS/IBS PAN (2013)
2. Billiet, C., Pons Frias, J.E., Pons Capote, O., De Tré, G.: A Comparison of Approaches to Model Uncertainty in Time Intervals. In: Pasi, G., Montero, J., Ciucci, D. (eds.) Advances in Intelligent Systems Research, pp. 626–633. Atlantis Press, Milano (2013)
3. Lecture Notes in Computer Science;C.S. Jensen,1998
4. Bronselaer, A., Pons, J.E., De Tré, G., Pons, O.: Possibilistic evaluation of sets. International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems 21(3), 325–346 (2013)
5. Chountas, P., Petrounias, I.: Modelling and Representation of Uncertain Temporal Information. Requirements Engineering 5(3), 144–156 (2000)