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            <bibl> <label>[1]</label> Hu W., Barkana, R., &amp; Gruzinov A. Phys. Rev. Lett. 85, 1158 -<lb/>1161 (2000), [astro-ph/0003365].<lb/></bibl>

            <bibl> <label>[2]</label> Matos T., and Siddhartha Guzman F. Class.Quant.Grav.17:L9-<lb/>L16,2000, [gr-qc/9810028].<lb/></bibl>

            <bibl> <label>[3]</label> Matos T., Siddhartha Guzman F., and Urena-Lopez L. A.<lb/> Class.Quant.Grav.17:1707-1712,2000, [astro-ph/9908152].<lb/></bibl>

            <bibl> <label>[4]</label> Matos T., and Urena-Lopez L. A. Phys.Rev.D63:063506,2001,<lb/> [astro-ph/0006024].<lb/></bibl>

            <bibl> <label>[5]</label> Garcia-Aspeitia M. A., and Matos, T. [gr-qc/0906.327].<lb/></bibl>

            <bibl> <label>[6]</label> Jae-Weon Lee and In-gyu Koh. Phys. Rev. D 53, 2236 -2239<lb/> (1996), [hep-ph/9507385].<lb/></bibl>

            <bibl> <label>[7]</label> Siddhartha Guzman F. Phys. Rev. D 73, 021501(R) (2006), [gr-<lb/>qc/0512081].<lb/></bibl>

            <bibl> <label>[8]</label> Bernal A., Matos T., Núñez D., 2008, RMxAA, 44, 149, [astro-<lb/>ph/0303455].<lb/></bibl>

            <bibl> <label>[9]</label> Matos T., Vazquez-Gonzalez A., and Magana J. [astro-<lb/>ph/0806.0683].<lb/></bibl>

            <bibl> <label>[10]</label> Böhmer C. G., and Harko T. JCAP06(2007)025, [astro-<lb/>ph/0705.4158v4].<lb/></bibl>

            <bibl> <label>[11]</label> Ferrer F., and Grifols J. A. JCAP12(2004)012, [astro-<lb/>ph/0407532].<lb/></bibl>

            <bibl> <label>[12]</label> Dodelson S. Modern Cosmology (Academic Press, 2003).<lb/></bibl>

            <bibl> <label>[13]</label> Kolb E. W., and Turner M. S. The Early Universe (Addison-<lb/>Wesley, 1990).<lb/></bibl>

            <bibl> <label>[14]</label> Lesgourgues J. and Pastor S. Physics Reports 429 (2006) 307 –<lb/> 379. [astro-ph/0603494].<lb/></bibl>

            <bibl> <label>[15]</label> Ma C., and Bertschinger E. Astrophys. J. 455, 7 (1995), [astro-<lb/>ph/9506072].<lb/></bibl>

            <bibl> <label>[16]</label> Woo T.P., and Chiueh T.C. ApJ 697 850-861, [astro-<lb/>ph/0806.0232].<lb/></bibl>

            <bibl> <label>[17]</label> Ureña-López L. A. Class. Quantum Grav. 19 2617-2632 (2002),<lb/> [gr-qc/0104093].<lb/></bibl>

            <bibl> <label>[18]</label> Ureña-López L. A. JCAP01(2009)014, [gr-qc/0806.3093].<lb/></bibl>

            <bibl> <label>[19]</label> Seljak<lb/> U.<lb/> and Zaldarriaga<lb/> M.<lb/> Astrophys.<lb/> J.<lb/> 469,<lb/> 437 (1996),<lb/> [astro-ph/9603033].<lb/> http://www.cfa.harvard.edu/∼mzaldarr/CMBFAST/cmbfast.html.</bibl>

        </listBibl>
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