Hempel, Peter; Mayer, Larry; Taylor, Elliott; Bohrmann, Gerhard; Pittenger, Alan (1989): The influence of biogenic silica on seismic lithostratigraphy at ODP Sites 642 and 643, eastern Norwegian Sea. Texas A & M University, Ocean Drilling Program, College Station, TX, United States, In: Eldholm, Olav, Thiede, Jorn, Taylor, Elliott, Barton, Colleen, Bjorklund, Kjell R., Bleil, Ulrich, Ciesielski, Paul F., Desprairies, Alain, Donnally, Diane M., Froget, Claude, Goll, Robert, Henrich, Rudiger, Jansen, Eystein, Krissek, Lawrence A., Kvenvolden, Keith A., LeHuray, Anne P., Love, David A., Lysne, Peter, McDonald, Thomas J., Mudie, Peta J., Osterman, Lisa E., Parson, Lindsay M., Phillips, Joseph D., Pittenger, Alan, Qvale, Gunnbjorg, Schoenharting, Guenther, Viereck, Lothar, Winkler, William R. (editor), Proceedings of the Ocean Drilling Program, Norwegian Sea; covering Leg 104 of the cruises of the Drilling Vessel JOIDES Resolution, Bremerhaven, Germany, to St. John's, Newfoundland, Sites 642-644, 19 June 1985-23 August 1985, 104, 941-951, georefid:1991-059173