How do you list volumes in docker containers?

When using docker images from registries, I often need to see the volumes created by the image’s containers.

Note: I’m using docker version 1.3.2 on Red Hat 7.

Example

The postgres official image from the Docker Registry has a volume configured for containers at /var/lib/postgresql/data.

What’s the most succinct command to show the volume at /var/lib/postgresql/data in a postgres container?