I need help cracking my own code

[Tarantino]

Hi everyone, I have a favour to ask. I have just been updating my Marvel and DC comic collection and when I made my original list I used a couple of abbreviations. As an example the following is how I typically listed a comic on my spreadsheets.

Action Comics – Superman (DC)   318   GD+   APT 1964 (CK)

The first part is obviously the title, DC is Detective Comics, 318 refers to the issue, GD+ is the grading meaning Good Plus. APT means it has the original American Price Tag and not the British 12p. 1964 is the year it came out  and for the life of me I cannot remember what (CK) means. I have added that for most of my comics but not all and I cannot remember what it refers to. Can anyone suggest what CK stands for in relation to my comic collection? It's going to bother me for the rest of my life if I don't find out.

Thank you in advance to whoever can figure it out.

Tarantino

[Tarantino]

Actually, I've just re-checked and every comic has CK next to it so that's confused me even more.

Thanks again.

Tarantino

[Dandontdare]

"Clark Kent" was the first that sprung to mind, but appearances by the mild-mannered reporter would be an odd indexing system.

Could C refer to Cover ... "cover (artist) known" maybe?

[Richard]

Could mean "check," as in you've checked you definitely have it and there are no gaps in your collection.

[Tarantino]

Wow, yes 'Checked' makes sense as each comic has it. It could very well mean that.

If no one else has any other suggestions I'm going take it to mean that :-)

Wow, I didn't think I would get an answer so quickly. The power of the collective mind is very powerful.

Oh and thanks Richard, you're a star.

Tarantino

[Tarantino]

And thanks to Dandontdare as well, but Clark Kent was a real long shot :-)

[The Legendary Shark]

CK