%0 Journal Article %A Auchmuty, G. %A Rivas, M.A. %T Unconstrained Variational Principles for Linear Elliptic Eigenproblems %J ESAIM: Control, Optimisation and Calculus of Variations %D 2015 %P 165-189 %V 21 %N 1 %I EDP-Sciences %U http://www.numdam.org/articles/10.1051/cocv/2014021/ %R 10.1051/cocv/2014021 %G en %F COCV_2015__21_1_165_0