@article{575216,
      recid = {575216},
      author = {Hellins, John,},
      title = {An extract from a letter of the Rev. Mr. John Hellins,  formerly assistant to Mr. (now Dr.) Maskelyne, the  Astronomer-Royal at Greenwich Observatory, to Francis  Maseres, Esq. Dated Potter's Pury, near Stoney Stratford,  in Buckinghamshire, Sept. 25, 1792. [electronic resource]  :},
      publisher = {s.n.,},
      address = {[London :},
      pages = {4p. ;},
      year = {1792},
      note = {Drop-head title.},
      url = {http://library.usi.edu/record/575216},
}