Error(s) in re-building vignettes:
  ...
duplicated vignette title:
  ‘Retrieving and Analyzing PubMed Records via easyPubMed’

--- re-building ‘easyPM_vignette_html.Rmd’ using rmarkdown
Quitting from lines 39-50 (easyPM_vignette_html.Rmd) 
Error: processing vignette 'easyPM_vignette_html.Rmd' failed with diagnostics:
1: StartTag: invalid element name
2: Input is not proper UTF-8, indicate encoding !
Bytes: 0xA2 0x40 0x98 0x3B
3: Opening and ending tag mismatch: PubmedData line 698 and Author
4: expected '>'
5: Opening and ending tag mismatch: Affiliation line 1117 and Affiliatioture
6: Opening and ending tag mismatch: AffiliationInfo line 1116 and AbstractText
7: Opening and ending tag mismatch: Author line 1112 and Abstract
8: Opening and ending tag mismatch: PubmedArticle line 443 and Article
9: Opening and ending tag mismatch: PubmedArticleSet line 3 and MedlineCitation
10: Extra content at the end of the document

--- failed re-building ‘easyPM_vignette_html.Rmd’

--- re-building ‘easyPM_vignette_pdf.Rmd’ using rmarkdown
Warning in for (i in seq_len(n)) { :
  closing unused connection 5 (https://eutils.ncbi.nlm.nih.gov/entrez/eutils/efetch.fcgi?db=pubmed&WebEnv=NCID_1_109516906_130.14.18.125_9001_1546452477_1831258843_0MetA0_S_MegaStore&query_key=1&retstart=0&retmax=500&rettype=null&retmode=xml)
Quitting from lines 39-50 (easyPM_vignette_pdf.Rmd) 
Error: processing vignette 'easyPM_vignette_pdf.Rmd' failed with diagnostics:
1: Input is not proper UTF-8, indicate encoding !
Bytes: 0xF2 0x02 0x99 0x3B
2: PCDATA invalid Char value 2
3: Opening and ending tag mismatch: Grant line 2359 and a
4: Opening and ending tag mismatch: GrantList line 2346 and Grant
5: Opening and ending tag mismatch: Article line 2265 and GrantList
6: Opening and ending tag mismatch: MedlineCitation line 2253 and Article
7: Opening and ending tag mismatch: PubmedArticle line 2252 and MedlineCitation
8: Opening and ending tag mismatch: ArticleIdList line 2708 and Reference
9: Opening and ending tag mismatch: Reference line 2706 and Abstract
10: Opening and ending tag mismatch: ReferenceList line 2549 and Article
11: Opening and ending tag mismatch: PubmedData line 2502 and MedlineCitation
12: Opening and ending tag mismatch: PubmedArticleSet line 3 and PubmedArticle
13: Extra content at the end of the document

--- failed re-building ‘easyPM_vignette_pdf.Rmd’

SUMMARY: processing the following files failed:
  ‘easyPM_vignette_html.Rmd’ ‘easyPM_vignette_pdf.Rmd’

Error: Vignette re-building failed.
Error: Duplicate vignette titles.
  Ensure that the %\VignetteIndexEntry lines in the vignette sources
  correspond to the vignette titles.
Execution halted