@article {MR3012900, title = {Spectral analysis for linear differential-algebraic equations}, journal = {Discrete Contin. Dyn. Syst.}, number = {Dynamical systems, differential equations and applications. 8th AIMS Conference. Suppl. Vol. II}, year = {2011}, pages = {991{\textendash}1000}, isbn = {978-1-60133-008-6; 1-60133-008-1}, issn = {1078-0947}, author = {Linh, Vu Hoang and Mehrmann, Volker} }