To find books in Quicksearch, start at https://library.yale.edu. Type your search terms into the box. I'm using the search term geologic strata because I want the system to know that I mean strata in the geologic sense — remember that the catalog is searching everything across all disciplines.

Once we are in Quicksearch, we can click Books+ just below the search box to view catalog records in general — book or otherwise.

Once we select Show Online Results Only in the left-hand menu, we will only see online materials. A new box with our limit will appear just above the results set.

We can use the same filter for online books to look for things that are not online. There is a small drop-down arrow next to the selected facet where we can select is not.

The screenshot below shows our results.

TIP: If you're searching for a book title, like Strata and Time: Probing the Gaps in Our Understanding, put the title in quotation marks — but split the quotation marks at the colon (:), as library records put a space before and after the colon. That makes our search "strata and time" "probing the gaps in our understanding" —