Need FM antenna solution

Hello All,
First of all, I must say that this was already posted on the RF-MW board, so I apologize if I annoy anyone.

We are trying to setup streaming FM radio for our small office network. For that we bought 3 AM/FM digital receivers, each tuned to a different station, which are connected to a PC with 3 sound cards (see pictures attached).

I'd like to have your opinion about:
1. What kind of antenna should I use for this setup? Single ended? differential?
2. Is the ground terminal of the receiver is where the antenna should be connected?
3. How should I split the antenna to three receivers?

Looking forward to your replies,
Thanks,
P.

Here's a link to the original message + pics
https://www.edaboard.com/viewtopic.p...038071#1038071