Checking the HEAD tag

Hi there,

I would like to know if it is possible to read the HEAG Tag or the BODY as i need to import my JS once (for a gallery).
Once i can see if that JS is here then i dont need to reinject it when i have 2 galleries.

I have a clue but just wanted to double check with others for a better solution.
Thanks a lot.

Regards,

Jerome