@article{MM2_1997__93_4_156294,
     author = {Masahiro Ohno},
     title = {On degenerate secant varieties of secant defect two.},
     journal = {Manuscripta mathematica},
     pages = {189--204},
     year = {1997},
     volume = {93},
     number = {4},
     zbl = {0910.14029},
     url = {http://geodesic.mathdoc.fr/item/MM2_1997__93_4_156294/}
}