docs: added citation information

CITATION.cff

@@ -1,11 +1,30 @@
 cff-version: 1.2.0
 message: "If you use this software, please cite it as below."
 authors:
-- family-names: "Pichler"
-  given-names: "Markus"
-  orcid: "https://orcid.org/0000-0002-8101-2163 "
-
-title: "idf_analysis: Intensity duration frequency analysis"
-version: 0.1.12
-date-released: 2022-05-28
-url: "https://github.com/MarkusPic/intensity_duration_frequency_analysis"
+  - family-names: Pichler
+    given-names: Markus
+    orcid: https://orcid.org/0000-0002-8101-2163
+    affiliation: Graz University of Technology
+title: "idf_analysis: Intensity duration frequency analysis with python based on KOSTRA"
+version: 0.2.4
+doi: 10.5281/zenodo.10559991
+date-released: 2024-01-24
+url: "https://github.com/MarkusPic/intensity_duration_frequency_analysis"
+license: MIT
+identifiers:
+  - description: This is the collection of archived snapshots of all versions of idf_analysis python package
+    type: doi
+    value: "10.5281/zenodo.10559991"
+  - description: This is the archived snapshot of version 0.2.4 of idf_analysis python package
+    type: doi
+    value: "10.5281/zenodo.10559992"
+keywords:
+ - kostra
+ - precipitation
+ - dwa-a-531
+ - Hydrology
+ - python
+ - statistics
+ - "extreme value analysis"
+ - "Extreme value theory"
+abstract: "heavy rain as a function of the duration and the return period acc. to DWA-A 531 (2012) This program reads the measurement data of the rainfall and calculates the distribution of the rainfall as a function of the return period and the duration for duration steps up to 12 hours (and more) and return period in a range of '0.5a <= T_n <= 100a'"

README.md

@@ -6,6 +6,7 @@
 
 [![license](https://img.shields.io/github/license/markuspic/intensity_duration_frequency_analysis.svg?style=flat)](https://github.com/MarkusPic/intensity_duration_frequency_analysis/blob/master/LICENSE)
 [![PyPI](https://img.shields.io/pypi/v/idf-analysis.svg)](https://pypi.python.org/pypi/idf-analysis)
+[![DOI](https://zenodo.org/badge/142560436.svg)](https://zenodo.org/doi/10.5281/zenodo.10559991)
 
 [![PyPI - Downloads](https://img.shields.io/pypi/dd/idf-analysis)](https://pypi.python.org/pypi/idf-analysis)
 [![PyPI - Downloads](https://img.shields.io/pypi/dw/idf-analysis)](https://pypi.python.org/pypi/idf-analysis)
@@ -39,6 +40,10 @@ This package was developed by [Markus Pichler](mailto:markus.pichler@tugraz.at)
 
 Read the docs [here 📖](https://markuspic.github.io/intensity_duration_frequency_analysis).
 
+## Please cite as
+
+Pichler, M. (2024). idf_analysis: Intensity duration frequency analysis with python based on KOSTRA (v0.2.4). Zenodo. https://doi.org/10.5281/zenodo.10559992
+
 ## Installation
 
 This package is written in Python3. (use a version > 3.5)