This source needs more explanation. It’s a frequent Hint -that’s a shaky leaf hint- on Ancestry. My first reaction was, ‘what a great resource, an index of all these published works.’ My second reaction was ‘what a scam, this is a bogus low quality source masked as a quality source.’ My third and current reaction is ‘what a great index providing paths to actual sources available on HathiTrust and Archive.org’- frequently with volume and page information included.

An example is Richard Smith b. 1589 in England. He has three separate AGBI hints. The page and volume numbers match only if I’m looking at the same edition and format referenced in the AGBI index. I wish the the full title, publisher and place of publication were provided in this AGBI index but its not so locating the referenced source can take time.

1. A genealogical dict. of the first settlers of New England, showing three generations of those who came before May, 1692. By James Savage. Boston. 1861. (4v.)v.4:326. Number 1 is at HathiTrust. https://catalog.hathitrust.org/Record/000276222  free, searchable easy copy/paste, save and download options. The Volume no. is correct Volume 4, page no. is way off. Smiths begin around page 120 and there are lots of Smiths. I read through about 7 ‘Richard Smiths’ (starting here) and did not find one that fit my Richard Smith. I’ve already ignored this AGBI hint on Ancestry and won’t add it to my tree. The value of the Hint is link it gives me to a possible great source. Number 1 was a dud, though. I’ve found no useable info here.
2. A recd. Of the achievements of her people in the making of a commonwealth and the founding of a nation. Ed. By Ezra S. Stearns. New York, 1908. (4v.):1621 Ancestors of Henry Montgomery Smith and Cath. Forshee. By Annie Morrill Smith. Brooklyn, NY. 1921. (139p.):49. Number 2 has 2 sources The first is also at HathiTrust. Ezra Stearns authored 2 volumes A recd. Of the achievements of her people in the making of a commonwealth and the founding of a nation, one for Connecticut and one for New Hampshire. Looking at both Volume 4 page 1621 I find nothing.  Since this will take a loooong time to decipher, I’ll save this Ancestry.com Hint in the Maybe category and come back to the Ezra Stearns books at some point.The second source is at HathiTrust, a different title: ‘Ancestors of Henry Montgomery Smith and Catherine Forshee, and their descendants to the present time’  I found it by author, on the exact page 49 https://babel.hathitrust.org/cgi/pt?id=wu.89066292632;view=1up;seq=55 but it’s not my 11th great grandfather Richard Smith who was only in Connecticut. The referenced Richard Smith was in Narragansett with Roger Williams and an original of the Bull Smith clan? and had a son connected with Andros, nope. I chose No for this Hint- it’s not for my tree.
3. Directory of the anc. heads of New England fams. Comp. By Frank R. Holmes. NewYork, 1923. (274p.):221. Number 3 is not a free online source. I can find it at Google books and World Cat but no free searchable copies- so I can’t evaluate the information right now. It is a book for check out at Open Library, I can join a waiting list. I’ll put this on hold. This same book probably also refers to the more famous Richard Smith of the time, not the Richard in my tree.