| 865 | A Guide To Reading and Writing Japanese (Florence Sakade) | 
| 804 | A Guide To Reading and Writing Japanese 3rd edition (Henshall, Seeley and De Groot) | 
| 783 | A Guide To Remembering Japanese Characters (Kenneth G. Henshall) | 
| 1050 | A New Dictionary of Kanji Usage | 
| 4255 | Classic Nelson (Andrew Nelson) | 
| 764 | Essential Kanji (P.G. O’Neill) | 
| 886 | Japanese Kanji Flashcards (Max Hodges and Tomoko Okazaki) | 
| 916 | Kanji and Kana (Spahn and Hadamitzky) | 
| 938 | Kanji and Kana, 2nd Edition (Spahn and Hadamitzky) | 
| 522 | Kanji in Context (Nishiguchi and Kono) | 
| 1636 | Kodansha Compact Kanji Guide | 
| 1565 | Kodansha Kanji Dictionary (Jack Halpern) | 
| 827 | Kodansha Kanji Learner’s Dictionary (Jack Halpern) | 
| 1132 | Kodansha Kanji Learner’s Dictionary, 2nd Edition (Jack Halpern) | 
| 476 | Les Kanjis dans la tete (Yves Maniette) | 
| 34417 | Morohashi | 
| 1222 | New Japanese English Character Dictionary (Jack Halpern) | 
| 5484 | New Nelson (John Haig) | 
| 465 | Remembering The Kanji (James Heisig) | 
| 504 | Remembering The Kanji, 6th edition (James Heisig) | 
| 802 | Tuttle Kanji Cards (Alexander Kask) | 
      duplicate, double, compound, multiple
    
    - On:
 - フク
 
      Jōyō kanji, taught in grade 5
    
    
      JLPT level N2
    
    
      915 of 2500 most used kanji in newspapers
    
Stroke order
On reading compounds
- 複 【フク】 compound, composite, multiple, re-, bi-, doubles (tennis, badminton, etc.), place bet (in horse racing, etc.), show bet, bet that predicts a top 2 or top 3 finish (depending on number of horses, etc. in race)
 - 複合 【フクゴウ】 composite, combined, complex
 - 重複 【チョウフク】 duplication, repetition, overlapping, redundancy, restoration
 - 遺伝子重複 【イデンシチョウフク】 gene duplication
 
Readings
- Korean:
 - bog, bu
 
Spanish
- repetir
 - duplicar
 - doble
 - compuesto
 - múltiple
 
Portuguese
- duplicação
 - duplicar
 - composto
 - múltiplo
 
French
- duplication
 - copie
 - composé
 - multiple
 - compliqué
 
| 667 | 2001 Kanji | 
| 5e9.3 | The Kanji Dictionary | 
| 1-5-9 | SKIP code | 
| 3824.7 | Four corner code | 
| 1-42-03 | JIS X 0208-1997 kuten code | 
| 8907 | Unicode hex code |