T. Ahmed-ali and F. Lamnabhi-lagarrigue, Sliding observer-controller design for uncertain triangular nonlinear systems, IEEE Transactions on Automatic Control, vol.44, issue.6, pp.1244-1249, 1999.

J. H. Ahrens and H. K. Khalil, High-gain observers in the presence of measurement noise, Automatica, vol.45, issue.4, pp.936-943, 2009.

M. Alamir, Optimization based non-linear observers revisited, International Journal of Control, vol.72, issue.13, pp.1204-1217, 1999.

A. Alessandri and A. Rossi, Increasing-gain observers for nonlinear systems: Stability and design, Automatica, vol.57, pp.180-188, 2015.

V. Andrieu, L. Praly, and A. Astolfi, High gain observers with updated gain and homogeneous correction terms, Automatica, vol.45, issue.2, pp.422-428, 2009.
URL : https://hal.archives-ouvertes.fr/hal-00362752

A. Astolfi and L. Praly, Global complete observability and output-tostate stability imply the existence of a globally convergent observer, Mathematics of Control, Signals, and Systems, vol.18, issue.1, pp.32-65, 2006.

G. Besançon and A. Ticlea, An immersion-based observer design for rank-observable nonlinear systems, IEEE Transactions on Automatic Control, vol.52, issue.1, pp.83-88, 2007.

D. Boskos and J. Tsinias, Sufficient conditions on the existence of switching observers for nonlinear time-varying systems, Eur. J. Control, vol.19, pp.87-103, 2013.

, Observer Design for Nonlinear Triangular Systems with Unobservable Linearization, International Journal of Control, vol.86, pp.721-739, 2013.

, Observer Design for a General Class of Triangular Systems, Proc. 21st Symp. Math. Theory Netw. Syst. (MTSN), 2014.

H. Du, C. Qian, S. Yang, and S. Li, Recursive design of finite-time convergent observers for a class of time-varying nonlinear systems, Automatica, vol.49, issue.2, pp.601-609, 2013.

P. Dufour, S. Flila, and H. Hammouri, Observer design for MIMO non-uniformly observable systems, IEEE Transactions on Automatic Control, vol.57, issue.2, pp.511-516, 2012.
URL : https://hal.archives-ouvertes.fr/hal-00648978

J. P. Gauthier, H. Hammouri, and S. Othman, A Simple Observer for Nonlinear Systems Applications to Bioreactors, IEEE Transactions on Automatic Control, vol.37, issue.6, pp.875-880, 1992.

J. Gauthier and I. Kupka, Deterministic Observation Theory and Applications, 2001.

T. Hò-ang, W. Pasillas-lépine, and W. Respondek, A switching observer for systems with linearizable error dynamics via singular time-scaling, Proc. 21st Symp. Math. Theory Netw. Syst. (MTNS), 2014.

I. Karafyllis and Z. P. Jiang, Hybrid dead-beat observers for a class of nonlinear systems, Systems and Control Letters, vol.60, issue.8, pp.608-617, 2011.

I. Karafyllis and C. Kravaris, Global exponential observers for two classes of nonlinear systems, Systems and Control Letters, vol.61, issue.7, pp.797-806, 2012.

D. Karagiannis, M. Sassano, and A. Astolfi, Dynamic scaling and observer design with application to adaptive control, Automatica, vol.45, issue.12, pp.2883-2889, 2009.

N. Kazantzis and C. Kravaris, Nonlinear observer design using Lyapunov's auxiliary theorem, Proceedings of the 36th IEEE Conference on Decision and Control, vol.5, pp.241-247, 1997.

J. Klamka, On the global controllability of perturbed nonlinear systems, IEEE Trans. Automat. Control, vol.20, issue.1, pp.170-172, 1975.

A. J. Krener and M. Xiao, Observers for linearly unobservable nonlinear systems, Systems and Control Letters, vol.46, issue.4, pp.281-288, 2002.

P. Krishnamurthy and F. Khorrami, Dynamic High-Gain Scaling: State and Output Feedback With Application to Systems With ISS Appended Dynamics Driven by All States, IEEE Trans. Autom. Control, vol.49, issue.12, pp.2219-2239, 2004.

T. Ménard, E. Moulay, and W. Perruquetti, Global finite-time observers for non linear systems, Proceedings of the IEEE Conference on Decision and Control, pp.6526-6531, 2009.

H. Ríos and A. R. Teel, A hybrid observer for fixed-time state estimation of linear systems, 2016 IEEE 55th Conference on Decision and Control (CDC), pp.5408-5413, 2016.

D. Theodosis, D. Boskos, and J. Tsinias, Observer design for triangular systems under weak observability assumptions, IEEE Transactions on Automatic Control, 2018.

J. Tsinias, Links between asymptotic controllability and persistence of excitation for a class of time-varying systems, Systems and Control Letters, vol.54, issue.11, pp.1051-1062, 2005.

, Time-varying observers for a class of nonlinear systems, Syst. Control Lett, vol.57, issue.12, pp.1037-1047, 2008.

J. Tsinias and D. Theodosis, Luenberger-type observers for a class of nonlinear triangular control systems, IEEE Trans. Autom. Control, vol.61, issue.12, pp.3797-3812, 2016.

Y. Yamamoto and I. Sugiura, Some sufficient conditions for the observability of nonlinear systems, J. Optim. Theory Appl, vol.13, issue.6, pp.660-669, 1974.