Paper  bibtex   

@article{
 title = {Second-order k"p perturbation theory with Vanderbilt pseudopotentials and plane waves},
 type = {article},
 year = {2000},
 pages = {4383-4388},
 volume = {62},
 id = {35f75f30-d334-3c04-89fa-36cb68ddb523},
 created = {2011-02-11T00:00:05.000Z},
 file_attached = {true},
 profile_id = {b9c5c1e6-09ce-3d53-9dcd-cde5fd0daa6e},
 group_id = {4a031295-8de8-39cf-9e88-45764d428e4b},
 last_modified = {2013-08-04T17:22:59.000Z},
 read = {false},
 starred = {false},
 authored = {false},
 confirmed = {true},
 hidden = {false},
 citation_key = {Pickard2000b},
 bibtype = {article},
 author = {Pickard, C J and Payne, M C},
 journal = {Physical Review B},
 number = {7}
}