The Droste Effect

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Across
  1. 2. TIMES Paper that resisted until 1942
  2. 5. British grid style
  3. 7. The year 1913
  4. 8. Horizontal direction
  5. 9. Richard / Cryptic pioneer
  6. 13. Rubber solver tool
  7. 14. Latin prefix for crossword
  8. 16. Vertical direction
  9. 17. Puzzle with hidden puns
  10. 21. First puzzle shape
  11. 22. Arthur / The inventor
  12. 23. The words in the grid
  13. 24. Margaret / First NYT editor
  14. 25. The unifying subject
Down
  1. 1. 180-degree rotation rule
  2. 3. Black and white layout
  3. 4. Related word puzzle type
  4. 6. One unit of the grid
  5. 10. The hint
  6. 11. Letters-in-a-box style
  7. 12. Graphite solver tool
  8. 15. The person doing it
  9. 18. Every letter A-Z used
  10. 19. NY World section name
  11. 20. SHORTZ Legendary editor
  12. 22. CROSS The original name