[244] K. Enqvist, A. Jokinen, A. Mazumdar, T. Multamaki, and A. Vaihkonen, Phys. Rev. Lett. 94 , 161301 (2005), astro-ph/0411394. [245] K. Enqvist, A. Jokinen, A. Mazumdar, T. Multamaki, and A. Vaihkonen, JCAP 0503 , 010 (2005), hep-ph/0501076. [246] K. Enqvist, A. Jokinen, A. Mazumdar, T. Multamaki, and A. Vaihkonen, JHEP 08 , 084 (2005), hep-th/0502185. [247] K. Kohri, D. H. Lyth, and C. A. Valenzuela-Toledo (2009), 0904.0793. [248] M. Sasaki and T. Tanaka, Prog. Theor. Phys. 99 , 763 (1998), gr-qc/9801017. [249] D. H. Lyth and Y. Rodriguez, Phys. Rev. D71 , 123508 (2005), astro-ph/0502578. [250] D. H. Lyth and Y. Rodriguez, Phys. Rev. Lett. 95 , 121302 (2005), astro-ph/0504045. [251] D. Wands, K. A. Malik, D. H. Lyth, and A. R. Liddle, Phys. Rev. D62 , 043527 (2000), astro-ph/0003278. [252] S. A. Kim and A. R. Liddle, Phys. Rev. D74 , 023513 (2006), astro-ph/0605604. [253] L. Kofman (2003), astro-ph/0303614. [254] G. Dvali, A. Gruzinov, and M. Zaldarriaga, Phys. Rev. D69 , 023505 (2004), astro- ph/0303591. [255] G. Dvali, A. Gruzinov, and M. Zaldarriaga, Phys. Rev. D69 , 083505 (2004), astro- ph/0305548. [256] K. Enqvist, A. Mazumdar, and M. Postma, Phys. Rev. D67 , 121303 (2003), astro- ph/0304187. [257] A. Mazumdar and M. Postma, Phys. Lett. B573 , 5 (2003), astro-ph/0306509. [258] D. N. Spergel et al. (WMAP), Astrophys. J. Suppl. 170 , 377 (2007), astro-ph/0603449. [260] J. Lesgourgues and W. Valkenburg, Phys. Rev. D75 , 123519 (2007), astro-ph/0703625. [259] L. Verde and H. V. Peiris, JCAP 0807 , 009 (2008), 0802.1219. [261] B. A. Powell and W. H. Kinney, JCAP 0708 , 006 (2007), 0706.1982. [262] R. Trotta, Contemp. Phys. 49 , 71 (2008), 0803.4089. [263] N. Bevis, M. Hindmarsh, M. Kunz, and J. Urrestilla, Phys. Rev. Lett. 100 , 021301 (2008), astro-ph/0702223. [264] U. Seljak and A. Slosar, Phys. Rev. D74 , 063523 (2006), astro-ph/0604143. [265] L. Pogosian and M. Wyman, Phys. Rev. D77 , 083509 (2008), 0711.0747. [266] N. Bevis, M. Hindmarsh, M. Kunz, and J. Urrestilla, Phys. Rev. D76 , 043005 (2007), 250