?url_ver=Z39.88-2004&rft_id=10.1007%2FBF01594922&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Gilbert%2C+J.C.&rft.aulast=Gilbert&rft.aufirst=J.C.&rft.issue=1-3&rft.volume=50&rft.date=1991&rft.issn=0025-5610&rft.atitle=Maintaining+the+positive+definiteness+of+the+matrices+in+reduced+secant+methods+for+equality+constrained+optimization&rft.title=Mathematical+Programming&rft.pages=1-28&rft.genre=article