X/1999 is a 10-book series with 10 primary works first released in 1992 with contributions by CLAMP and Fred Burke.
1992 • 2 Readers • 5
1993 • 2 Readers • 5
1993 • 2 Readers • 5
1993 • 2 Readers • 5
1994 • 2 Readers • 184 pages • 5
1995 • 3 Readers • 5
1996 • 2 Readers • 5
1997 • 3 Readers • 5
1999 • 3 Readers • 192 pages • 5