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Help : About databases

Frequently asked questions

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Q
What can I search by the NDL Online ?
A
You can search for the materials held by the NDL, including books, periodicals and newspapers published inside and outside Japan, electronic resources, rare books and old materials, doctoral dissertations, maps, audio-visual materials, standards and technical reports. Digital contents (Digitized materials, E-Journals, etc.) and The Japanese Periodicals Index can also be searched via the NDL Online. For details, please refer to "NDL Online help."

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Q
What is the difference between NDL Search and NDL Online?
A
Since NDL Online searches for materials in the National Diet Library holdings and digital contents, it is useful when searching for National Diet Library's collections or when applying for remote copying services.
In contrast, NDL Search runs integrated searches for materials from the collections of various institutions across Japan, including public, university, and special libraries, as well as archives, museums, and academic research institutions.

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Q
Are all articles from periodicals searchable in the Japanese Periodicals Index (JPI)?
A
Only articles published in periodicals selected and indexed by the Library in the JPI (indexed periodicals) are searchable. For names of periodicals and the start and stop dates of indexing for periodical issues, please check the "List of Indexed Periodicals in the Japanese Periodicals Index" (in Japanese). Selection of indexed periodicals is conducted in accordance with the "Japanese Periodicals Index Periodical Selection Criteria". In addition to this, selection of articles in selected and indexed periodicals is conducted in accordance with the "Japanese Periodicals Index Article Selection and Indexing Criteria". Please note that the scope of indexed periodicals has changed over time.

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Q
Am I able to read digitized materials from articles I've searched in the Japanese Periodicals Index (JPI)?
A
For periodical articles that “To bibliographic records of digitized materials” link is displayed in the bibliographic record of NDL Online, you may read these as digitized materials only within the Tokyo Main Library, the Kansai-kan Library, the International Library of Children's Literature, and on the site of the partner libraries.
When you click on the “To bibliographic records of digitized materials” link, the bibliographic record for the issue of the periodical that contains the article will be displayed. Click on the “Digital” button displayed in the bibliographic record, the text of the periodical will be displayed as a digital image.

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Q
Please increase the number of periodicals searchable in the Japanese Periodicals Index (JPI).
A
The JPI has consistently expanded its indexed periodicals up to this point. At present, the JPI lists about 10,000 academic journals, technical journals, and general interest magazines. The number is being expanded on a regular basis by selecting newly published periodicals.
For names of periodicals and the start and stop dates of indexing for periodical issues, please check the "List of Indexed Periodicals in the Japanese Periodicals Index" (in Japanese). Selection of indexed periodicals is conducted in accordance with the "Japanese Periodicals Index Periodical Selection Criteria".

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