@article{Bergman_1977,
    doi = {10.1007/bf02485443},
    url = {https://doi.org/10.1007%2Fbf02485443},
    year = {1977},
    month = {dec},
    publisher = {Springer Science and Business Media {LLC}},
    volume = {7},
    number = {1},
    pages = {341--356},
    author = {George M. Bergman},
    title = {On the existence of subalgebras of direct products with prescribedd-fold projections},
    journal = {Algebra Universalis}
}

@article{Bergman_1977, doi = {10.1007/bf02485443}, url = {https://doi.org/10.1007%2Fbf02485443}, year = {1977}, month = {dec}, publisher = {Springer Science and Business Media {LLC}}, volume = {7}, number = {1}, pages = {341--356}, author = {George M. Bergman}, title = {On the existence of subalgebras of direct products with prescribedd-fold projections}, journal = {Algebra Universalis} }