Turn off grid / list view as it creates duplicate pages on google - bad for seo

hi there
version 3.9
can anyone tell me how i can stop google indexing grid and list view for category pages?
I believe this setting will create duplicate pages which is very bad for seo.

i.e

i believe google spiders one category i.e "Toys" as 3 seperate DUPLICATE epages

https://www.website/en/toys?viewmode=grid
https://www.website/en/toys?viewmode=list
https://www.website/en/toys

any ideas?

Thanks !

hi all, anyone know how to do this?

toadman wrote:

This link contains good information:

https://support.google.com/webmasters/answer/93710?hl=en