ECOREGIONS OF THE CONTERMINOUS UNITED-STATES

[11] Omermk J. M., 1982, PLACE RESOURCE INVEN, P199

[12] Omernik J.M., 1977, EPA600377105 CORV EN

[13] TOTAL ALKALINITY OF SURFACE WATERS - A NATIONAL MAP [J]. ANNALS OF THE ASSOCIATION OF AMERICAN GEOGRAPHERS, 1983, 73 (01) : 133 - 136

[14] TOTAL ALKALINITY OF SURFACE WATERS - A MAP OF THE UPPER MIDWEST REGION OF THE UNITED-STATES [J]. ENVIRONMENTAL MANAGEMENT, 1986, 10 (06) : 829 - +

[15] OMERNIK JM, 1985, EPA600D84216 CORV EN

[16] ECOLOGICAL LAND CLASSIFICATION - A SURVEY APPROACH [J]. ENVIRONMENTAL MANAGEMENT, 1981, 5 (05) : 451 - 464

[17] Trewartha G. T, 1943, INTRO WEATHER CLIMAT

[18] *US BUR CENS, 1969, CENS AGR 15, V5

[19] *US BUR CENS, 1974, CENS AGR 1, V4

[20] *US BUR CENS, 1978, CENS AGR 1, V5

[11] Omermk J. M., 1982, PLACE RESOURCE INVEN, P199

[12] Omernik J.M., 1977, EPA600377105 CORV EN

[13] TOTAL ALKALINITY OF SURFACE WATERS - A NATIONAL MAP [J]. ANNALS OF THE ASSOCIATION OF AMERICAN GEOGRAPHERS, 1983, 73 (01) : 133 - 136

[14] TOTAL ALKALINITY OF SURFACE WATERS - A MAP OF THE UPPER MIDWEST REGION OF THE UNITED-STATES [J]. ENVIRONMENTAL MANAGEMENT, 1986, 10 (06) : 829 - +

[15] OMERNIK JM, 1985, EPA600D84216 CORV EN

[16] ECOLOGICAL LAND CLASSIFICATION - A SURVEY APPROACH [J]. ENVIRONMENTAL MANAGEMENT, 1981, 5 (05) : 451 - 464

[17] Trewartha G. T, 1943, INTRO WEATHER CLIMAT

[18] *US BUR CENS, 1969, CENS AGR 15, V5

[19] *US BUR CENS, 1974, CENS AGR 1, V4

[20] *US BUR CENS, 1978, CENS AGR 1, V5