Copyright © 2011 L. Berezansky and E. Braverman. This is an open access article distributed under the
Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Existence of positive solutions for advanced equations with several terms is investigated in the following three cases: (a) all coefficients are positive; (b) all coefficients are negative; (c) there is an equal number of positive and negative coefficients. Results on asymptotics of nonoscillatory solutions are also presented.