P3D Is it 50s or 50's?

["Dr. George A. Themelis" <DrT-3d@xxxxxxxxxxxxxxxxxxxxxxxxxxx>]

Silly but important question for me:  When we talk about the
50s (the glorious day of "do it yourself stereo") is it proper
to write 50's or just 50s?

I used to write 50's but someone - an editor - correct it to 
50s ... but that doesn't look right... is it right?

Thank you! -- George Themelis


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