
PhD thesis by Hawking's student Friedel Epple, titled: String scattering amplitudes and effective action for toroidal orientifolds
2006
2006
1988
2011
1926
1976-1977
1980-1984
2006
1982
2010
1999
1999
1998
1995
1997
1996
1986
1985
1990
1986
1995
1982
1988
2004
1984
1973
2007
2010
2001
1975
1982
1993
2016
1928
1999
1941
1977
1985
1989
1975
1931
1996
1970
1986
circa 1987
1936
1973
1992
1972
1979
1923