@article{89954,
      author       = "Fokina, Ekaterina,  B. and Friedman, Sy D.  and Centre de
                      Recerca Matemàtica ",
      title        = "<a
                      href="/search?f=title&p=On%20%5Bsummation%20of%201%20raised%20to%20the%20power%201%5D%20equivalence%20relations%20over%20the%20natural%20numbers&sc=1&ln=en">On
                       [summation of 1 raised to the power 1] equivalence
                      relations over the natural numbers</a>",
      year         = "2011",
}