ppt
http://thelightekphrastic.com/issues/february-2013-issue-13/crosfield-purvis-february-2013/
http://thelightekphrastic.com/issues/august-2014-issue-19/beckemeyer-and-wood-aug-2014/
http://thelightekphrastic.com/issues/august-2013-issue-15/nohe-galligan-august-2013/
http://thelightekphrastic.com/issues/august-2010-issue-3/toll-moss-aug-10/