Need help identifying artist

Hello!
I bought this abstract charcoal drawing at auction in Portugal (so the artist is probably portuguese), and I need help identifying the signature. Any ideas? Thanks.
(Sorry for the bad photo I haven't had time to get a clear image of it)

 

A photograph of the back please and close-ups of any stickers, labels or handwritten notations.

Debora

 

Where in Portugal? What auction house?

Debora

 

Do you read the date as "abril 1944" or "abril 1994"?

Debora

 

This appears to be done on newsprint, to my eye. If that is the case, the acid will continue to slowly degrade the paper and cause it to get very brittle. You should use caution if you decide to re-frame so as not to tear it.

The mat looks like it is also not acid-free.

 

I'll try and get a photo of the back when I can, and there aren't any labels or marks except for a watermark that reads "Matos".

It was just a local one near the capital, Lisbon.

I'm not sure about the date, the auction house suggested 1974 aswell.

 

Perhaps they suggested abril 1974 because of this.

https://en.wikipedia.org/wiki/Carnation_Revolution

Debora