if(NOT LIBIONOBASE_IS_EXTERNAL_PROJECT)
  set(LIBIONOBASE_PREFIX "" CACHE PATH "The path to the prefix of an libionobase installation")

  find_path(
    LIBIONOBASE_INCLUDE_DIRS
    NAMES ionobase/interchfor.hpp
    PATHS ${LIBIONOBASE_PREFIX}/include)
  find_library(
    LIBIONOBASE_LIBRARY
    NAMES ionobase
    PATHS ${LIBIONOBASE_PREFIX}/lib)

  if(LIBIONOBASE_INCLUDE_DIRS AND LIBIONOBASE_LIBRARY)
    get_filename_component(LIBIONOBASE_LIBRARY_DIR ${LIBIONOBASE_LIBRARY}
                           DIRECTORY CACHE)
    set(LIBIONOBASE_FOUND TRUE)
  endif()

  if(LIBIONOBASE_FOUND)
    if(NOT LIBIONOBASE_FIND_QUIETLY)
      message(STATUS "Found libionobase")
    endif()
    set(HAVE_LIBIONOBASE 1)
  elseif(LIBIONOBASE_FOUND)
    if(LIBIONOBASE_FIND_REQUIRED)
      message(FATAL_ERROR "Could not find libionobase")
    endif()
  endif()
endif()