# APA References

```{admonition} User types
:class: tip
This page is useful for user type 4 and 5.
```

{bdg-primary}`(To be converted into) Sphinx Extension`

```{warning}
The instructions provided here are stable, but because it relies on a local extension that is part of your book files and _not_ managed as part of a computing environment (e.g., `pip` or `conda`), there may be incompatibility with other features. For example, the draft-release workflow does not work.

We are actively working on improving this. Visit the [project page on GitHub](https://github.com/orgs/TeachBooks/projects/17) to learn more.

This page will be updated when a solution is available.
```

## Introduction

Do you include references in your book, but you're tired of the default options available in Jupyter Book? For example, the square-bracket style of citation and reference, where the first three letters of the name year are combined in a way that seems designed to minimize transparency?

There is a solution! This extension allows you to have APA formatting in your book.

## Installation
To use APA-references, a set of Python files need to be manually loaded into your book

**Step 1: files to root directory of your book**

Download this zip-file [`_ext.zip`](_ext.zip), which contains the necessary files, unzip it and place the contents in the root of your book directory so that it looks like the schematic here:

```
book
├── _ext/
│   ├── pybtexapastyle/
│   ├── apastyle.py
│   ├── bracket_citation_style.py
├── _config.yml
├── _toc.yml
├── requirements.txt
├── <book files>
```

**Step 2: Add to `requirements.txt`**

Add a specific version of `docutils` to your requirements file:
```
docutils==0.17.1
```

**Step 3: Enable in `_config.yml`**

In your `_config.yml` file, add a `bibtex_default_style`, `bybtex_reference_style` and the local extensions `apastyle` and `bracket_citation_style.py`
```
sphinx:
  config:
    ...
    bibtex_default_style: myapastyle
    bibtex_reference_style: author_year_round
  local_extensions:
    apastyle: _ext/
    bracket_citation_style: _ext/
  ...
```

## Usage

All references are now made in APA-style. See for example this reference: {cite:t}`jason_moore` which shows up on the [references page](../references.md) too. The form of the citation looks like this:

```
{cite:t}`jason_moore`
```

Here are three examples for making citations:

| Syntax | Result |
| :---: | :---: |
|`{cite:t}` | {cite:t}`jason_moore` |
|`{cite:p}`| {cite:p}`jason_moore` |
|`{cite}`| {cite}`jason_moore` |

For more options on the in-line citation style, see https://jupyterbook.org/en/stable/content/citations.html#change-the-in-line-citation-style.

### Known Issue

During the build, warning will be raised with `... WARNING: duplicate label for keys ...`. In most cases, these warnings can be ignored. As noted above, the book will not build references properly 

## Implementation

The extension is based on [`pybtex`](https://pybtex.org/), which is a BibTeX-compatible bibliography processor in Python that is extendible with plugins. 

Although some customization is possible with the standard Jupyter Book features, [as described here](https://jupyterbook.org/en/stable/content/citations.html#change-the-in-line-citation-style), this extension implements the complete APA style, as well as enforcing round brackets (like this).

The need to enforce `docutils==0.17.1` version is the only known solution to the issue where empty brackets `[]` are left on the references page.

## Contribute

This tool needs to be developed further to make it into a proper sphinx-extension (and/or an independent `pybtext` plugin). The process is described in this [project page on GitHub](https://github.com/orgs/TeachBooks/projects/17). If you've ideas or questions, please reach out to us at info@teachbooks.io!