Where can I found Firmware-copter-stable-3.5.3?

Hi,everyone, where can I download 3.5.3 version? There is no 3.5.3 version now in http://firmware.ardupilot.org/Copter . Why delete this version? Is not stable?

Please use the latest stable ChibiOS 3.6.9
It meets real-time better than NuTuX 3.5.3

Thanks.I need copter-stable-3.5.3 firmware ,other versions not good for me

use git to checkout the release tag and compile the code localy.