Tutorial 5: Add bibliography reference section (#28)

* Update hash of thumbnail figure for Tutorial 5

Wish there was more human readable URLs...

* Fix references and add bibliography to Tutorial 5

Got several `WARNING: could not find bibtex key` errors because a Bibliography section wasn't put in. Xref https://jupyterbook.org/en/stable/content/citations.html

Author: weiji14

book/_config.yml

@@ -44,6 +44,7 @@ html:
 
 sphinx:
   config:
+    bibtex_bibliography_header: ".. rubric:: References"
     bibtex_reference_style: author_year
     html_show_copyright: false
     # Adjust highlight language for sphinx_gmt examples

book/intro.md

@@ -95,7 +95,7 @@ and [Yvonne Fröhlich](https://orcid.org/0000-0002-8566-0619)
 :gutter: 1
 
 :::{grid-item-card} Tutorial 5 - 3-D Topography (Planetary / Antarctic maps)
-:img-top: _images/1dfddce0ff606bd7dc3a175aedbd2fc4bde3aeadfadfd339eb30ce1903d049f9.png
+:img-top: _images/0a6fc097b1fcaa99eff8632dab714787757564ed60e07f20825101c6a8e045ae.png
 :link: ./tut05_topography.html
 by [Wei Ji Leong](https://orcid.org/0000-0003-2354-1988)
 and [André Belém](https://orcid.org/0000-0002-8865-6180)

book/tut05_topography.ipynb

@@ -418,6 +418,9 @@
     "- https://github.com/andrebelem/PlanetaryMaps/blob/main/2_%20Tutorial%20Mars%20Maps%20V2.ipynb\n",
     "- https://www.generic-mapping-tools.org/egu22pygmt/lidar_to_surface.html\n",
     "- https://www.pygmt.org/v0.13.0/tutorials/advanced/3d_perspective_image.html\n",
+    "```\n",
+    "\n",
+    "```{bibliography}\n",
     "```"
    ]
   }