@article{SM_2000_191_11_a4,
     author = {N. V. Timofeeva},
     title = {The homology groups of the variety of complete pairs $X_{13}$ of zero-dimensional subschemes of lengths~1 and~3 of projective space},
     journal = {Sbornik. Mathematics},
     pages = {1693--1705},
     year = {2000},
     volume = {191},
     number = {11},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2000_191_11_a4/}
}