CMake cannot install imported targets
Refer: https://cmake.org/Bug/view.php?id=14311
It is desirable to be able to install an imported target, add it to an export set and export the same.
add_library(prebuilt STATIC IMPORTED) set_property(TARGET prebuilt PROPERTY IMPORTED_LOCATION ${CMAKE_CURRENT_SOURCE_DIR}/libprebuilt.a)
install(TARGETS other_built_targets prebuilt EXPORT project-export RUNTIME DESTINATION bin LIBRARY DESTINATION lib ARCHIVE DESTINATION lib )
Making prebuilt an imported target makes in convenient to use in the project and treats it further like any other target.