'osmium/index/map/vector.hpp' file not found when making

[kkkondo]

Hi,
I got an error 'osmium/index/map/vector.hpp' file not found when making:

$ make
Scanning dependencies of target osm-routing-bgl
[ 16%] Building CXX object src/CMakeFiles/osm-routing-bgl.dir/GraphBuilder.cpp.o
In file included from /Users/kkkondo/git/osm-routing-bgl/src/GraphBuilder.cpp:2:
/Users/kkkondo/git/osm-routing-bgl/include/GraphBuilder.h:7:10: fatal error: 
      'osmium/index/map/vector.hpp' file not found
#include <osmium/index/map/vector.hpp>
         ^
1 error generated.
make[2]: *** [src/CMakeFiles/osm-routing-bgl.dir/GraphBuilder.cpp.o] Error 1
make[1]: *** [src/CMakeFiles/osm-routing-bgl.dir/all] Error 2
make: *** [all] Error 2
$ 
$ ls /usr/local/include/osmium/index/map/
all.hpp                dummy.hpp              sparse_mem_map.hpp
dense_file_array.hpp   flex_mem.hpp           sparse_mem_table.hpp
dense_mem_array.hpp    sparse_file_array.hpp  sparse_mmap_array.hpp
dense_mmap_array.hpp   sparse_mem_array.hpp   
$
$ brew info libosmium
libosmium: stable 2.15.0
Fast and flexible C++ library for working with OpenStreetMap data
https://osmcode.org/libosmium/
$

libosmium has been install through homebrew as shown above.