Pop Stars of the 60s

The other day I had a clear-out of all the old cards I'd received since moving into my flat more than 20 years ago.

I looked at every single one of them, sent for a variety of occasions - birthday, mother's day, get well, retirement, thank you, bon voyage - before putting them into the recycling bin. All except the cards from the two daughters.

I thought this random one, sent as a birthday card, would make a nostalgic blip for those of us who remember the great 60s era of pop music. 

Am I right in thinking The Beatles are conspicuous in their absence?