sccs & make

[looi at sutro.SFSU.EDU]

If you have a source file "mod.c" in SCCS,
how does the makefile know where to find it.
Do you have to make a special notation in the
makefile to let the makefile know where to find
the mod.c source file for compilation purposes?
Example:
dummy:   $ try
try:     mod.o
        cc try.c -o try

mod.o:  
        cc -c mod.c

When I run this makefile I get:
xlc: 1501-228 input file mod.c not found.