Tried installing said module using cpanm Net::SSH::Perl to no avail. Got to Math::GMP and bailed out. Am using PerlBrew on Linux with Perl 5.19. Amazingly, I have never had this happen before. The resultant log file shows of a subsequent install attempt of Math::GMP yielded the following my question which is:
where would I expect to find gmp.h, and why would it not be there?

(I have not done the --force yet as it does not seem to me like one should have to)

Thanks for any enlightenment..

cpanm (App::cpanminus) 1.7001 on perl 5.019010 built for x86_64-linux
Work directory is /home/wjw/.cpanm/work/1399045680.9633
You have make /usr/bin/make
You have LWP 6.06
You have /bin/tar: tar (GNU tar) 1.26
Copyright (C) 2011 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gp
+l.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by John Gilmore and Jay Fenlason.
You have /usr/bin/unzip
Searching Math::GMP on cpanmetadb ...
--> Working on Math::GMP
Fetching http://www.cpan.org/authors/id/T/TU/TURNSTEP/Math-GMP-2.07.ta
+r.gz
-> OK
Unpacking Math-GMP-2.07.tar.gz
Entering Math-GMP-2.07
Checking configure dependencies from META.yml
Configuring Math-GMP-2.07
Running Makefile.PL
Checking if your kit is complete...
Looks good
Generating a Unix-style Makefile
Writing Makefile for Math::GMP
Writing MYMETA.yml and MYMETA.json
-> OK
Checking dependencies from MYMETA.json ...
Checking if you have ExtUtils::MakeMaker 0 ... Yes (6.98)
Building and testing Math-GMP-2.07
cp lib/Math/GMP.pm blib/lib/Math/GMP.pm
AutoSplitting blib/lib/Math/GMP.pm (blib/lib/auto/Math/GMP)
Running Mkbootstrap for Math::GMP ()
chmod 644 GMP.bs
/home/wjw/perl5/perlbrew/perls/perl-5.19.10/bin/perl5.19.10 /home/wjw/
+perl5/perlbrew/perls/perl-5.19.10/lib/5.19.10/ExtUtils/xsubpp  -typem
+ap /home/wjw/perl5/perlbrew/perls/perl-5.19.10/lib/5.19.10/ExtUtils/t
+ypemap -typemap typemap  GMP.xs > GMP.xsc && mv GMP.xsc GMP.c
cc -c   -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/incl
+ude -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -O2   -DVERSION=\"2.07
+\" -DXS_VERSION=\"2.07\" -fPIC "-I/home/wjw/perl5/perlbrew/perls/perl
+-5.19.10/lib/5.19.10/x86_64-linux/CORE"   GMP.c
GMP.xs:4:17: fatal error: gmp.h: No such file or directory
compilation terminated.
make: *** [GMP.o] Error 1
-> FAIL Installing Math::GMP failed. See /home/wjw/.cpanm/work/1399045
+680.9633/build.log for details. Retry with
--force to force install it.
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