zookeeper/NOTICE.txt

Apache ZooKeeper
Copyright 2009-2020 The Apache Software Foundation

This product includes software developed at
The Apache Software Foundation (http://www.apache.org/).

This product includes software components originally
developed for Airlift (https://github.com/airlift/airlift),
licensed under the Apache 2.0 license. The licensing terms
for Airlift code can be found at:
https://github.com/airlift/airlift/blob/master/LICENSE