Cannot compile simple code

[mramalingam2203]

I installed the library via ubuntu packages and it seems the header files need to be included in the compilation:
g++ code.cpp -I/home/muthu/Documents/work/kickback/libspatialaudio/include -I/home/muthu/Documents/work/kickback/libspatialaudio/include/hrtf -I/home/muthu/Documents/work/kickback/libspatialaudio/source/kiss_fft -lspatialaudio

While some of the functions of the object could be linked some could not be. The error is like this:
/usr/bin/ld: /tmp/ccQTjiik.o: in function main': code.cpp:(.text+0x115): undefined reference to CAmbisonicEncoder::SetPosition(PolarPoint, float)'
/usr/bin/ld: code.cpp:(.text+0x182): undefined reference to `CAmbisonicDecoder::Configure(unsigned int, bool, unsigned int, int, unsigned int)'

May I know how it can be resolved?

collect2: error: ld returned 1 exit status