Some books do not have an ISBN that is easily identifiable. Books published prior to the mid-1970's may not have an ISBN at all. Using the Pre-ISBN Search Tool, you can try entering some details in the form above and we can try to find other books like it that are available online.
These books are for sale on other marketplaces, so they won't have an immediate buyer, but we'll try to show you how long it will take to sell if you choose to list it. Keep in mind that these are just estimates based on recent sales history. Additionally, if you sell on a marketplace, fees of about 20% will be deducted, and it may take a few weeks to actually receive payment.