Longley, P. A. (2015). Geographic information science & systems (4th ed.). John Wiley & Sons.
Chicago-čujuhus (17. p.)Longley, Paul A. Geographic Information Science & Systems. 4th ed. Hoboken, NJ: John Wiley & Sons, 2015.
MLA-čujuhus (9. p.)Longley, Paul A. Geographic Information Science & Systems. 4th ed. John Wiley & Sons, 2015.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.