RISC RISC Research Institute for Symbolic Computation  
  • @techreport{RISC1465,
    author = {Erik Hillgarter and G\"unter Landsmann and Josef Schicho and Franz Winkler},
    title = {{Generalized Offsets as Envelopes of a One-parameter Set of Spheres}},
    number = {99-27},
    year = {1999},
    month = {September},
    keywords = {canal surface, sum of two squares},
    sponsor = {Austrian Science Fund (FWF), Proj.Nr. P11160-TEC (HySax), Proj.Nr. P12662-TEC (Adjoints), and the special research area SFB F013, subprojects 03 and 04.},
    type = {RISC Report Series},
    institution = {Research Institute for Symbolic Computation (RISC), Johannes Kepler University Linz},
    address = {Schloss Hagenberg, 4232 Hagenberg, Austria}