Published in Physical Review D 81, 084023 (2010) (2010) [E-print]

Published in Classical and Quantum Gravity 27, 084034 (2010) [E-print]

Published in Physical Review D 79, 064018 (2009) [E-print]

Published in Proceedings of 18th Workshop on General Relativity and Gravitation in Japan (JGRG18), 17-21 (2009) [E-print]

Published in Classical and Quantum Gravity 26, 015007 (2008) [E-print]

Published in Classical and Quantum Gravity 25, 145018 (2008) [E-print]

Published in Phys. Rev. D 77, 101501(R) (2008) [E-print]

Published in Physical Review D 78, 024039 (2008) [E-print]

Published in Phys. Rev. D 77, 024034 (2007) [E-print]

Published in Class. Quant. Grav. 25, 195019 (2007) [E-print]