waiting for a response

[Ginso]

Hello,
16 days ago, i wrote a mail to a publisher asking for a game license and he hasn't responded yet.
How long would you wait before contacting them again, and how would you do it?
It's a small german(like me) publisher and the website only provides an email adress and a phone number.

[Tisaac]

It might be due to the summer vacations, I would wait mid september before asking them again.