Размещение файлов заголовков в подкаталоге каталога / usr / include with automake?

If I write a library, and have header files for development included, and have a src/Makefile.am like this:

AM_CFLAGS = -std=c99 -Wall -Werror -Os
lib_LTLIBRARIES = libmylibrary.la
libmylibrary_la_SOURCES = a.c b.c
include_HEADERS = a.h b.h

Everything works nicely. However, a.h and b.h are installed directly under /usr/include (or /usr/local/include). What should I do to get them installed, in a subdirectory specific to my library, e.g. /usr/include/mylibrary?