add tutorial "How to turn ancient calendar sources into absolute dates"

CONTRIBUTORS.yaml

@@ -968,6 +968,12 @@ gauravsharma:
     github: false
     joined: 2026-01
 
+gautschr:
+    gtn-halloffame: "no"
+    name: Rita Gautschy
+    github: true
+    joined: 2026-06
+
 geraldinevanderauwera:
     gtn-halloffame: "no"
     name: Geraldine Van der Auwera

topics/digital-humanities/tutorials/ancient-calendar-sources/faqs/index.md

@@ -0,0 +1,3 @@
+---
+layout: faq-page
+---

topics/digital-humanities/tutorials/ancient-calendar-sources/tutorial.bib

@@ -0,0 +1,35 @@
+
+# This is the bibliography file for your tutorial.
+#
+# To add bibliography (bibtex) entries here, follow these steps:
+#  1) Find the DOI for the article you want to cite
+#  2) Go to https://doi2bib.org and fill in the DOI
+#  3) Copy the resulting bibtex entry into this file
+#
+# To cite the example below, in your tutorial.md file
+# use {% cite Gautschy2011 %}
+#
+# If you want to cite an online resourse (website etc)
+# you can use the 'online' format (see below)
+#
+# You can remove the examples below
+
+@article{Gautschy2011,
+  doi = {10.1524/zaes.2011.0002},
+  url = {https://doi.org/10.1524/zaes.2011.0002},
+  year = {2011},
+  publisher = {De Gruyter},
+  volume = {138},
+  number = {1},
+  pages = {1--19},
+  author = {Rita Gautschy},
+  title = {Monddaten aus dem Archiv von Illahun: Chronologie des Mittleren Reiches},
+  journal = {Zeitschrift f\"{u}r \"{a}gyptische Sprache und Altertumskunde}
+}
+
+@online{Gautschy-mond,
+  author = {Rita Gautschy},
+  title = {Lunar Dates / Monddaten},
+  url = {https://www.gautschy.ch/%7Erita/archast/mond/mondeng.html},
+  urldate = {2026-06-25}
+}