Character Encoding

A wide variety of characters appear in Taylor & Francis journal content, owing to the international nature of our journals. The Unicode character set is to be used for all TF JATS XML. Unicode contains the characters of most of the world's scripts, and is also the standard character set for XML.

Many different systems and software packages are involved in the creation and processing of Taylor & Francis content. Simply using UTF-8 in each XML file would not guarantee accurate preservation of character data. A very specific set of rules for encoding character data, described here, should be adhered to in the creation of all TF JATS XML files. These rules aim for the highest degree of compatibility, and least opportunity for data corruption, when files are transferred and processed on different systems.

Each TF JATS XML file should declare ISO646-US as the character encoding in the XML declaration.

<?xml version="1.0" encoding="ISO646-US"?>

Only characters from the subset of Unicode that is ISO646-US, also known as US-ASCII or "keyboard characters", should be present in the XML file. These characters are considered by Unicode to be "safe" characters that should display in any software application. The characters that comprise ISO646-US are (in character code order):

!"#%&'()*+,-./
0123456789
:;<=>?@
ABCDEFGHIJKLMNOPQRSTUVWXYZ
[\]^_`
abcdefghijklmnopqrstuvwxyz
{|}~
            

In addition to this set, legal XML whitespace characters are allowed. Legal XML whitespace characters are:

\x20  (space)
\x9   (tab)
\xD   (carriage return)
\xA   (line feed)
            

Unicode characters outside of the characters listed above must be coded as XML character entities. Either numeric character entities in hex form (&) or decimal form (&), or named character entities (&) may be used. Character codes used in numeric character entities (character references) must refer to a specific character in the Unicode character set.

Hawaiʻi
Hawai&okina;i

The TF JATS DTD includes all named character entities defined by the W3C's ISO and MathML entity sets, and a large number of additional character entities for common characters. A table showing all of the named character entities defined in the TF JATS DTD is available here.

To help locate the numeric character code for any particular character the code charts provided at unicode.org and unicodelookup.com are useful references. In addition, many editing programs provide special character choosers, and some XML software will automatically convert characters to XML character entities.

Note that two characters from the list of ISO646-US characters, the ampersand (&) and the less-than sign (<), when they appear in text must be coded as XML character entities to meet the well-formedness requirements of XML. The entity forms of the ampersand have been given above, and the entity forms of the less-than sign are &#x3C;, &#60;, and &lt;.

Although Unicode contains the characters of most of the world's scripts and is an expanding standard, there are some characters or glyphs that are not available in Unicode. When characters not available in Unicode are encountered the character, or string of characters, should be captured as a graphic file and tagged using <inline-graphic>. See the image guidelines for more information on this.