TTS engne for Lithuanian language synthesation based on LIEPA project (https://www.xn--ratija-ckb.lt/liepa/infrastrukturines-paslaugos/elektroninio-teksto-skaitytuvas/7563)
Arabisc is speaker independent large vocabulary continuous speech recognizer for Arabic language released under GNU license.It is also a collection of open source tools that allows researchers and developers to build speech recognition systems for Arab
Scalable Language API (SLAPI) The most comprehensive architecture for conversational natural-language applications including speech recognition/synthesis, semantics, & machine translation. Used on Android & other mobile app platforms.
The Open VXI VoiceXML interpreter is a portable open source library that interprets the VoiceXML dialog markuplanguage. It is designed to serve as a reference for parties interested in understanding how VoiceXML markup might be executed.