@TechReport{di-fcul-tr-04-15,
    author = {Daniel Gomes and André L. Santos and Mário J. Silva},
    title = {Webstore: A Manager for Incremental Storage of Contents},
    institution = {Department of Informatics, University of Lisbon},
    month = {November},
    year = {2004},
    type = {DI/FCUL TR},
    number = {04--15},
    url = {http://www.di.fc.ul.pt/tech-reports/04-15.pdf}
}