Seems to be a pain to install, so here are notes, for me later, and for anyone else.
You'll need some packages from Debian sid proper. Create a file /etc/apt/sources.list.d/debiansid.list
with the following content (this will be a temporary step, which you undo later).
deb http://ftp.us.debian.org/debian sid main
Then import its keys.
apt-get install debian-archive-keyring
You'll have to say "y" to "Install these packages without verification?" Indeed, I do not consider myself paranoid.
sudo apt-get install libgnutls-deb0-28 libhiredis0.10 libicu52 libmemcached11
cd Downloads
wget http://ftp.indexdata.dk/pub/yaz/ubuntu/14.10/libyaz5_5.11.0-1.indexdata_i386.deb
wget http://ftp.indexdata.dk/pub/yaz/ubuntu/14.10/yaz_5.11.0-1.indexdata_i386.deb
sudo dpkg -i yaz_5.11.0-1.indexdata_i386.deb libyaz5_5.11.0-1.indexdata_i386.deb
After this, make sure you remove the added Debian source, to avoid breaking your system next time you update packages. Either remove the file /etc/apt/sources.list.d/debiansid.list
or just add #
before its main contents line.