$prefix = '_sitename_';

    $year_select_array = array();
    for ($i=date('Y')+1; $i >= 1900 ; $i--) {
        $year_select_array[$i] = $i;
    }

    $default_text_field_columns = 200; //the max width will fix it if it's too big

    $meta_boxes[] = array(
        'id'         => 'reference-citation',
        'title'      => 'Citation',
        'post_types' => 'reference',
        'context'    => 'after_editor',
        'priority'   => 'high',

        'fields' => array(
            array(
                'name'            => 'Publication Type',
                'id'              => $prefix . 'publication_type',
                'type'            => 'select',
                // Array of 'value' => 'Label' pairs
                'options' => array(
                    'article' => 'Article',
                    'book' => 'Book',
                    'book-chapter' => 'Book Chapter',
                    'presentation' => 'Presentation',
                ),
                // Placeholder text
                'std' => 'article',
            ),
            array(
                'name' => 'Title',
                'id'   => $prefix . 'article_title',
                'type' => 'text',
                'size' =>  $default_text_field_columns,
                'desc' => 'Add article, chapter or presentation title',
                'visible'  => array(
                    'when' => array(
                        array( $prefix . 'publication_type', '=', 'article'),
                        array( $prefix . 'publication_type', '=', 'book-chapter'),
                        array( $prefix . 'publication_type', '=', 'presentation')
                     ),
                    'relation' => 'or'
                )
            ),
            array(
                'name' => 'Publication Title',// Book title, or Journal title
                'desc' => 'Add journal or book title',
                'id'   => $prefix . 'publication_title',
                'type' => 'text',
                'size' =>  $default_text_field_columns,
                'visible' => array(
                    'when' => array(
                        array( $prefix . 'publication_type', '=', 'article'),
                        array( $prefix . 'publication_type', '=', 'book'),
                        array( $prefix . 'publication_type', '=', 'book-chapter'),
                    ),
                    'relation' => 'or'
                )
            ),
            array(
                'name' => 'Author(s)',
                'id'   => $prefix . 'author',
                'type' => 'text',
                'size' =>  $default_text_field_columns
            ),

            array(
                'id'   => $prefix . 'editor',
                'type' => 'text', // New HTML 5 input type
                'name' => 'Editors(s)',
                'size' =>  $default_text_field_columns,
                'visible' =>  array( $prefix . 'publication_type', '=', 'book-chapter'),
            ),
            array(
                'id'   => $prefix . 'publisher',
                'type' => 'text', // New HTML 5 input type
                'name' => 'Publisher',
                'size' =>  $default_text_field_columns,
                'visible' => array(
                    'when' => array(
                        array( $prefix . 'publication_type', '=', 'book'),
                        array( $prefix . 'publication_type', '=', 'book-chapter'),
                    ),
                    'relation' => 'or'
                )
            ),
            array(
                'name' => 'Publication City',
                'desc' => 'Add the city where the publisher is based or where the presentation took place',
                'id'   => $prefix . 'publication_city',
                'type' => 'text',
                'size' =>  $default_text_field_columns,
                'visible' => array(
                    'when' => array(
                        array( $prefix . 'publication_type', '=', 'book'),
                        array( $prefix . 'publication_type', '=', 'book-chapter'),
                        array( $prefix . 'publication_type', '=', 'presentation'),
                    ),
                    'relation' => 'or'
                )
            ),
            array(
                'id'   => $prefix . 'volume_issue_number',
                'type' => 'fieldset_text', // New HTML 5 input type
                'name' => 'Volume(Issue)',
                'class' => 'volume-issue-fieldset',
                'options' => array(
                    'volume'    => 'Volume',
                    'issue' => 'Issue',
                ),
                'visible' => array($prefix . 'publication_type', '=', 'article'),
            ),
            array(
                'id'   => $prefix . 'page_number',
                'type' => 'text', // New HTML 5 input type
                'name' => 'Page Number(s)',
                'size' =>  $default_text_field_columns,
                'visible' => array(
                    'when' => array(
                        array( $prefix . 'publication_type', '=', 'article'),
                        array( $prefix . 'publication_type', '=', 'book-chapter'),
                    ),
                    'relation' => 'or'
                )
            ),
            array(
                'name'            => 'Publication year',
                'id'              => $prefix . 'publication_year',
                'type'            => 'select',
                // Array of 'value' => 'Label' pairs
                'options' => $year_select_array,
                // Placeholder text
                'placeholder'     => 'Select a year',
            ),
        )
    );

return $meta_boxes;