Updated jupyter notebook and readme file.

 # Schupbach 2018 Example
 # Schupbach 2018 Example
+This example is based on three figures from an article by 
+[Schupbach et al.](./nature.comm.2018/mcconnell-nature-communications-2018.pdf)
+that appeared in Nature Communications, 16 April 2018.
 
 
-The paper this example is
-from
-[Schupbach 2018](./nature.comm.2018/mcconnell-nature-communications-2018.pdf).
-
-# Dependencies
-
-This example requires the seaborn package.  You can install the
-package by typing the following.
-
-```sh
-pip install seaborn
-```
+## Source Data
+- All files (paper as pdf, datasets, figures, and supplementary information)
+  were downloaded from [www.nature.com](https://www.nature.com/articles/s41467-018-03924-3)
+  on 30 March 2019.  
 
 
+## Problem Statement and Objective
+- As closely as possible, reproduce Figures 1-3 as published in Nature using 
+  the datasets provided by the authors.  
 
 
+## Paper Reference: 
+- Greenland records of aerosol source and atmospheric lifetime changes from 
+  the Eemian to the Holocene
+- S. Schüpbach, H. Fischer, M. Bigler, T. Erhardt, G. Gfeller, D. Leuenberger, 
+  O. Mini, R. Mulvaney, N. J. Abram, L. Fleet, M. M. Frey, E. Thomas, A. Svensson, 
+  D. Dahl-Jensen, E. Kettner, H. Kjaer, I. Seierstad, J. P. Steffensen, 
+  S. O. Rasmussen, P. Vallelonga, M. Winstrup, A. Wegner, B. Twarloh, K. Wolff, 
+  K. Schmidt, K. Goto-Azuma, T. Kuramoto, M. Hirabayashi, J. Uetake, J. Zheng, 
+  J. Bourgeois, D. Fisher, D. Zhiheng, C. Xiao, M. Legrand, A. Spolaor, 
+  J. Gabrieli, C. Barbante, J.-H. Kang, S. D. Hur, S. B. Hong, H. J. Hwang, 
+  S. Hong, M. Hansson, Y. Iizuka, I. Oyabu, R. Muscheler, F. Adolphi, O. Maselli, 
+  J. McConnell & E. W. Wolff
+- Nature Communications, volume 9, Article number: 1476 (2018)