Knox, John A.; Rackley, Jared A.; Black, Alan W.; Gensini, Vittorio A.; Butler, Michael; Dunn, Corey; Gallo, Taylor; Hunter, Melyssa R.; Lindsey, Lauren; Phan, Minh; Scroggs, Robert; Brustad, Synne. Tornado Debris Characteristics and Trajectories During the 27 April 2011 Super Outbreak as Determined Using Social Media Data. Bulletin of the American Meteorological Society. 2013, 94 (9): 1371–1380. Bibcode:2013BAMS...94.1371K. doi:10.1175/BAMS-D-12-00036.1.
Knox, John A.; Rackley, Jared A.; Black, Alan W.; Gensini, Vittorio A.; Butler, Michael; Dunn, Corey; Gallo, Taylor; Hunter, Melyssa R.; Lindsey, Lauren; Phan, Minh; Scroggs, Robert; Brustad, Synne. Tornado Debris Characteristics and Trajectories During the 27 April 2011 Super Outbreak as Determined Using Social Media Data. Bulletin of the American Meteorological Society. 2013, 94 (9): 1371–1380. Bibcode:2013BAMS...94.1371K. doi:10.1175/BAMS-D-12-00036.1.
New Tornado Records Set for Alabama. National Weather Service in Birmingham, Alabama. National Oceanic and Atmospheric Administration. [November 1, 2011]. (原始内容存档于August 6, 2011).
New Tornado Records Set for Alabama. National Weather Service in Birmingham, Alabama. National Oceanic and Atmospheric Administration. [November 1, 2011]. (原始内容存档于August 6, 2011).