Download png image in shinyapps.io

Hi, I have a simple question : I would download a png image with my application on shinyapps.io but in the log file I have the following message : File www/iris.png not found in resource path, whereas the file and the folder are correct. My code is the following :

Sidebar-Density {.sidebar data-weight=300}
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**Introduction:** The Iris flower data set or Fisher's Iris data set is a 
multivariate data set introduced by the British statistician and biologist 
Ronald Fisher in his 1936 paper 
(Source : [wikipedia](https://en.wikipedia.org/wiki/Iris_flower_data_set))

![](www/iris.png){#id .class width=100% height=70%}

Could you help me ? Thanks in advanced