IPC Published 16 Tammy Specials at 1 a year between 1971 and 1986. They had many slightly different titles:
1971 - Tammy and Sally Holiday Special
1972 - Tammy Summer Special
1973 & 1974 - Tammy and Sandie Summer Special
1975 - Tammy and June Summer Special
1976 & 1977 - Tammy Summer Special
1978-1986 - Tammy Holiday Special