| Clue | Source | Date |
|---|---|---|
| Paperback IDs | ||
| Library IDs | Universal | 27 Oct 2024 |
| IDs on copyright pages | LA Times Daily | 11 Jun 2024 |
| Barnes & Noble nos. | Wall Street Journal | 13 Apr 2024 |
| Library IDs | LA Times Daily | 10 Sep 2023 |
| 13-digit pub. codes | LA Times Daily | 11 Apr 2023 |
| Nos. for librarians | Wall Street Journal | 26 Feb 2022 |
| Library IDs | New York Times | 19 Dec 2021 |
| Publishing IDs | New York Times | 17 Jun 2021 |
| Book IDs | Wall Street Journal | 15 May 2021 |
| Amazon IDs | New York Times | 19 Nov 2020 |
| Library IDs | Universal | 04 Nov 2020 |
| Book marks? | Wall Street Journal | 01 Feb 2020 |
| 13-digit pub. codes | The Washington Post | 02 Dec 2019 |
| 13-digit pub. codes | LA Times Daily | 02 Dec 2019 |
| Book IDs | LA Times Daily | 22 Sep 2019 |
| Book IDs | The Washington Post | 22 Sep 2019 |
| 13-digit book IDs | USA Today | 13 Jun 2019 |
| 13-digit book IDs | ||
| Book IDs | ||
| Amazon IDs | ||
| Info in a 1-Across | New York Times | 06 May 2016 |
| Publishing IDs | Universal | 21 Sep 2015 |
| Publishing IDs | ||
| IDs in book publishing | ||
| Amazon.com nos. | ||
| Dust-jacket IDs | ||
| Amazon.com nos. | ||
| Publishing IDs | ||
| 13-digit IDs | ||
| 10-digit book IDs | ||
| Publishing IDs |