https://www.google.ca/search?q=A+diminished+7&rlz=1C1AVSX_enUS415CA416&espv=210&es_sm=122&tbm=isch&tbo=u&source=univ&sa=X&ei=VpqYUpLJAffLsQSU7ICYBQ&ved=0CDYQsAQ&biw=1366&bih=638
Adim7 chord: second row down, fourth 'picture' from the left side of page.