* The British Library: The British Library's website contains a large collection of digitized lullabies from around the world. These lullabies can be searched by language, region, or keyword, and can be viewed online or downloaded in PDF format.
* The Library of Congress: The Library of Congress's website contains a large collection of American lullabies. These lullabies can be searched by title, author, or keyword, and can be viewed online or downloaded in PDF format.
* Google Books: Google Books contains a large collection of books about lullabies. These books can be searched by title, author, or keyword, and can be read online or purchased in print form.
* WorldCat: WorldCat is a union catalog that contains records for books and other materials held in libraries around the world. WorldCat can be used to find books about lullabies that are available in your local library or through interlibrary loan.