I need about 10 sturdy boxes to mail items to the USA. The boxes the post office sells are too small, I need file boxes strong enough to hold books. Does anyone know where I can purchase such boxes?

Thanks,
amevango

Hi - if you go to the Philippine shop on badenerstr just past LindenPlatz, they sell really strong boxes called Balikbayan Box which we use to send charity items (including books) abroad. We also used these when we moved home.
Problem is that they cost at least 10chf each.
I have not been for over a year now, so it would be worth telephoning first.
The last number I had was
PHILEXPRESS GMBH
Badenerstr. 710
8048 Zürich
Tel. 01/433 32 01

Or try the famous Banana boxes at the local Migros, Coop for free.