The original Liero data and binary files are copyright 1998 Joosa Riekkinen
They are, unless otherwise stated, available under the WTFPL license:
<http://sam.zoy.org/wtfpl/>

The LIERO.EXE binary contains the SMIX sound library:
<http://homepages.cae.wisc.edu/~brodskye/smix/smix.html>
The author of SMIX has stated that it is available under a BSD-3-Clause license,
with a request for donations for use in commercial products.

LIERO.SND contains sounds from Molez:
<http://www.fractilegames.com/product.php?id=molez>
Molez is freeware and freely distributable.

The license in LIEROENG.TXT is no longer valid but the file is kept for nostalgic purposes ;)