Also check out Mellel for iPad - Mellel for Mac’s young, able and nimble brother product.

Mellel comes equipped with a unique set of tools, allowing you to control every aspect of your footnotes, track changes, cross-reference, table of contents, citations, text boxes, images, bibliography, sorting, styles, lists, and so on - while keeping things well in control via its superb Outline pane.

FEATURES
General
• A real work-horse: Mellel will remain agile and reliable writing a simple letter or a 400 pages long manuscript with hundreds of notes, images, citations, text boxes, headings and cross-references
• Reliability: Mellel works as promised. It doesn't crash, nor will it harm your documents. If you're looking for a tool to trust your valuable manuscript with - Mellel is it
• True multilingual support: Multilingual support is not an afterthought with Mellel: it was written from the ground up as a multilingual word processor. You’ll find in it the best support for languages such as Arabic, Hebrew and Syriac, not to mention Japanese, Korean, Chinese, Greek, Cyrillic languages, and more

Advanced Writing Tools
• Footnotes and Endnotes: Mellel offers the best set of tools for footnotes and endnotes, with quality layout and control over every aspects of notes - including unique features such as support for multiple note streams
• Cross Reference: Mellel offers the best support for cross-references, bar none. You can reference anything, anywhere in your document, with amazing ease and flexibility and instant updating
• Headings and titles: A superb tool allowing you to set the style, numbering, repeating elements, multi-part headings, and much more
• Bibliography support: Mellel offers superb support for citations, including Live Bibliography, scan and un-scan, smart styling of citations, manuscript and final citations, and a host of other advanced bibliography features
• Table of contents: Mellel allows you to design your table of contents, set exactly how it will look, ordered and what it will include, and update your ToC in a matter of seconds
• Paragraph control: Allows you to control and style alignment, spacing before and after, margins, hyphenation, keep with next, and many other features
• Text and Character: With Mellel you can easily control how your text will look, from text stroke to baseline shift to the colour, thickness and shape of your double underline
• Text boxes: Insert text boxes, align them anywhere you like, set background and frames, corner radius, and flow text around the text box
• Word Count: Mellel doesn't just count words, it also allows you to set what to count, and enumerate citations, tables, images, headings and footnotes
• Images: Set wrapping of text around images, frame, fill, opacity and many other features. A big plus, it actually works instead of messing up your document
• Running headers: have your headers change with the chapters and sub-chapters in the document

Manage Your Document
• Outline: allows you to view your entire document, organise and reorder it
• Track Changes: track changes from multiple sources, and collaborate with multiple editors and writers
• Find and replace: Mellel supports a regular-expression-like language, and also allows you to save find actions and organise them in sets you can easily run to make multiple changes
• Style sets: enables you to manage and streamline your page, column, note, list, paragraph, and character styles - and keep them consistent between documents

Compatibility: OS X 10.6 or later

More info - https://itunes.apple.com/us/app/mellel/id415467848?mt=12