DSP e 21
on this page 2012-11-03
All photos © Heikki Siltala.
The photos are immediately available both for non-commercial and commercial uses under the Creative Commons Attribution 3.0 License
. There is no need to get a more specific permission or to pay money. The attribution is Heikki Siltala
. The earlier www.heikkisiltala.com
is also allowed.