cloverleaf secondary structure search program

[Robert J. Felber]

Dear Netters,

I am looking for a program, which is able to detect potential cloverleaf
secondary structures (potential tRNAs) for a MS-DOS computer. I found
one in the literature: 'TRNA', developed by Staden (1980) Nucleic Acid
Research 8, 817-825.
Does anyone know, from where I can get it or if there is a modern equivalent.
For any hints I would be very appreciated. Thanks in advance.

Robert J.