Using a static library

[schnitzel]

you just add this to your .pro file:

for windows:
LIBS += path/to/your/lib/libnewmat.a

for unix:

LIBS += -L/usr/local/lib -lnewmat

Make sure you put that new lib in /usr/local/lib for the example above.

I find it useful to do the following command on the final executable:

ldd ./mynewapp

this will give you a list of all libs the app needs and whether it was able to find them all.