?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aulast=Wall&rft.aufirst=TE&rft.au=Wall%2C+TE&rft.date=1+May+2015&rft.atitle=Selective+production+of+Rydberg-stark+states+of+positronium&rft.volume=114&rft.issue=17&rft.title=Physical+Review+Letters&rft.issn=1079-7114&rft.genre=article