Hi, I need help compiling rsbml package on linux ubuntu 18.04

I get following error:

BioC_mirror: https://bioconductor.org
Using Bioconductor 3.7 (BiocInstaller 1.30.0), R 3.5.1 (2018-07-02).
Installing package(s) ‘rsbml’
trying URL 'https://bioconductor.org/packages/3.7/bioc/src/contrib/rsbml_2.38.0.tar.gz'
Content type 'application/x-gzip' length 623814 bytes (609 KB)
==================================================
downloaded 609 KB
* installing *source* package ‘rsbml’ ...
checking for pkg-config... /usr/bin/pkg-config
checking pkg-config is at least version 0.9.0... yes
checking for LIBSBML... no
configure: error: Package requirements (libsbml >= 3.0.2) were not met:
No package 'libsbml' found

the libsbml is there and works for matlab and python. the r libSBML interface is also there. what else can I do? Thanks in advance!

As stated in the previous thread, please make sure PKG_CONFIG_PATH is set to point to the directory containing libsbml.pc.