The United States Geological Survey recognizes two contrasting definitions of a river's source.USGS.gov By the stricter definition, the Mississippi would share its source with its longest tributary, the Missouri, at Brower's Spring in Montana. The other definition acknowledges "somewhat arbitrary decisions" and places the Mississippi's source at Lake Itasca, which is publicly accepted as the source,USGS.gov and which had been identified as such by Brower himself.MT.govАрхивирано на сајту Wayback Machine (18. јануар 2012)
Angert, Joe and Isaac. „Old River Control”. The Mighty Mississippi River. Архивирано из оригинала 15. 5. 2009. г. Приступљено 12. 5. 2011. Includes map and pictures.
The United States Geological Survey recognizes two contrasting definitions of a river's source.USGS.gov By the stricter definition, the Mississippi would share its source with its longest tributary, the Missouri, at Brower's Spring in Montana. The other definition acknowledges "somewhat arbitrary decisions" and places the Mississippi's source at Lake Itasca, which is publicly accepted as the source,USGS.gov and which had been identified as such by Brower himself.MT.govАрхивирано на сајту Wayback Machine (18. јануар 2012)
The United States Geological Survey recognizes two contrasting definitions of a river's source.USGS.gov By the stricter definition, the Mississippi would share its source with its longest tributary, the Missouri, at Brower's Spring in Montana. The other definition acknowledges "somewhat arbitrary decisions" and places the Mississippi's source at Lake Itasca, which is publicly accepted as the source,USGS.gov and which had been identified as such by Brower himself.MT.govАрхивирано на сајту Wayback Machine (18. јануар 2012)
Angert, Joe and Isaac. „Old River Control”. The Mighty Mississippi River. Архивирано из оригинала 15. 5. 2009. г. Приступљено 12. 5. 2011. Includes map and pictures.
