Nearly all of items during the pamphlet selection have data in LocatorPlus. The many pre-1801 and about fifty,000 19th and 20th century pamphlets don't but have information in LocatorPlus. Many of them can be found by browsing in the Index-Catalogue with the Library of your Surgeon-General’s Office Whichever I see https://letsbookmarkit.com/story19262582/the-greatest-guide-to-%E4%B8%AD%E5%8C%BB-velocity