user9992: It is difficult for me to find the reference about Gautama Buddha wore robe made from cloth which was wrapped to a death body. Which part of Sutta do I have to reference? 
Can we calculate how long Buddha wore this? 

user701: It is in  SN 16.11.

‘Your outer robe of patches is soft, Kassapa.’–‘Venerable sir, let the Blessed One accept my outer robe of patches, out of compassion.’–‘Then will you wear my worn-out hempen rag-robes? ’–‘I will, venerable sir.’ Thus I offered the Blessed One my outer robe of patches and received from him his worn-out hempen rag-robes.

However, the English translation doesn't mention that the Buddha wore a cloth wrapped to a dead body instead it just mentions worn-out hempen rag-robes. In the pali version it says the robe was paṃsukūlāni (rags discarded on the ground). 
The Buddha has obtained it from the dead body of a servant named Punna lying in the cemetery (this part is in the commentary). He wore this robe until he exchanged it with Maha Kassapa. 

9992: <p>It is difficult for me to find the reference about Gautama Buddha wore robe made from cloth which was wrapped to a death body. Which part of Sutta do I have to reference? </p>

<p>Can we calculate how long Buddha wore this? </p>
 701: <p>It is in  <a href="https://suttacentral.net/en/sn16.11" rel="nofollow noreferrer">SN 16.11</a>.</p>

<blockquote>
  <p>‘Your outer robe of patches is soft, Kassapa.’–‘Venerable sir, let the Blessed One accept my outer robe of patches, out of compassion.’–‘Then will you wear my worn-out hempen rag-robes? ’–‘I will, venerable sir.’ Thus I offered the Blessed One my outer robe of patches and received from him his worn-out hempen rag-robes.</p>
</blockquote>

<p>However, the English translation doesn't mention that the Buddha wore a cloth wrapped to a dead body instead it just mentions <em>worn-out hempen rag-robes</em>. In the pali version it says the robe was <em>paṃsukūlāni</em> (rags discarded on the ground). </p>

<p>The Buddha has obtained it from the dead body of a servant named Punna lying in the cemetery (this part is in the commentary). He wore this robe until he exchanged it with Maha Kassapa. </p>
