| Keyword | CPC | PCC | Volume | Score | Length of keyword |
|---|---|---|---|---|---|
| historical sources are materials by nature | 1.94 | 1 | 4608 | 85 | 42 |
| historical | 1.18 | 1 | 7809 | 88 | 10 |
| sources | 2 | 0.8 | 7698 | 44 | 7 |
| are | 1.57 | 0.1 | 28 | 8 | 3 |
| materials | 1.84 | 0.6 | 926 | 26 | 9 |
| by | 1.09 | 0.2 | 7815 | 78 | 2 |
| nature | 1.96 | 0.3 | 1329 | 59 | 6 |
| Keyword | CPC | PCC | Volume | Score |
|---|---|---|---|---|
| historical sources are materials by nature | 1.88 | 0.5 | 9051 | 86 |
| what are the historical sources | 1.71 | 0.7 | 4222 | 10 |
| material sources of history | 0.27 | 0.3 | 2306 | 31 |
| what are the types of historical sources | 0.42 | 0.6 | 5713 | 84 |
| sources of historical facts | 1.65 | 0.6 | 5970 | 30 |
| kinds of historical sources | 0.35 | 0.2 | 7284 | 73 |
| these are original historical sources | 1.82 | 0.7 | 5183 | 61 |
| sources of historical information | 0.13 | 0.6 | 8608 | 10 |
| what are history and historical sources | 1.18 | 0.6 | 1916 | 66 |
| what are sources in history | 0.63 | 0.5 | 5020 | 3 |
| material sources of history images | 0.25 | 0.5 | 2258 | 94 |
| nature of a source history | 0.34 | 0.3 | 6178 | 81 |
| type of sources in history | 1.06 | 0.4 | 394 | 13 |
| sources of modern history | 1.62 | 1 | 4848 | 7 |
