@InCollection{Libson95a,
    author = {J. Libson and J. Mass{\'o} and E. Seidel and W.-M. Suen},
    title = {A 3D Apparent Horizon Finder},
    year = {1996},
    pages = {631},
    note = {PHY94-07882,PHY94-04788,ASC93-18152},
    editor = {R. T. Jantzen and G. M. Keiser and R. Ruffini},
    address = {Singapore},
    publisher = {World Scientific},
    booktitle = {The Seventh Marcel Grossmann Meeting: On Recent Developments in Theoretical and Experimental General Relativity, Gravitation, and Relativistic Field Theories}
}