N. Barnaby, und J. Cline. (2008)cite arxiv:0802.3218
Comment: 26 pages, 5 figures; references added, sign convention for f_NL
clarified, minor corrections.
L. Alabidi, und J. Lidsey. (2008)cite arxiv:0807.2181
Comment: 10 pages, 5 figures, revtex4. Figures, table and text updated to
match the version that has been accepted to Phys Rev D.
W. Kinney, und K. Tzirakis. (2007)cite arxiv:0712.2043
Comment: 10 pages, LaTeX; V2: version submitted to PRD. References added,
minor error in text corrected.
L. Leblond, und S. Shandera. (2008)cite arxiv:0802.2290
Comment: 26 pages, 4 figures, v3; added references and clarifications, typos
corrected, published version.