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

--- re-building ‘easyPM_vignette_html.Rmd’ using rmarkdown
Warning in grep("\\\n$", msg) :
  input string 1 is invalid in this locale
Quitting from lines 39-50 (easyPM_vignette_html.Rmd) 
Error: processing vignette 'easyPM_vignette_html.Rmd' failed with diagnostics:
1: Input is not proper UTF-8, indicate encoding !
Bytes: 0xF0 0x43 0x10 0xA9
2: PCDATA invalid Char value 16
3: Opening and ending tag mismatch: Citation line 934 and Reference
4: expected '>'
5: Opening and ending tag mismatch: ReferenceList line 746 and PubmedData
6: Opening and ending tag mismatch: PubmedData line 704 and PubmedArticle
7: PCDATA invalid Char value 2
8: PCDATA invalid Char value 1
9: PCDATA invalid Char value 1
10: PCDATA invalid Char value 1
11: PCDATA invalid Char value 2
12: PCDATA invalid Char value 28
13: PCDATA invalid Char value 26
14: PCDATA invalid Char value 4
15: PCDATA invalid Char value 30
16: PCDATA invalid Char value 2
17: PCDATA invalid Char value 1
18: PCDATA invalid Char value 21
19: PCDATA invalid Char value 16
20: PCDATA invalid Char value 14
21: PCDATA invalid Char value 26
22: PCDATA invalid Char value 8
23: PCDATA invalid Char value 16
24: PCDATA invalid Char value 6
25: PCDATA invalid Char value 2
26: PCDATA invalid Char value 3
27: PCDATA invalid Char value 1
28: PCDATA invalid Char value 4
29: Opening and ending tag mismatch: AffiliationInfo line 1628 and AuthorList
30: Opening and ending tag mismatch: Author line 1621 and Article
31: Opening and ending tag mismatch: AbstractText line 1617 and MedlineCitation
32: PCDATA invalid Char value 16
33: Opening and ending tag mismatch: Abstract line 1616 and PubmedArticle
34: Couldn't find end of Start Tag ISOAb line 3427
35: PCDATA invalid Char value 6
36: PCDATA invalid Char value 1
37: PCDATA invalid Char value 1
38: PCDATA invalid Char value 5
39: PCDATA invalid Char value 5
40: PCDATA invalid Char value 19
41: PCDATA invalid Char value 17
42: PCDATA invalid Char value 6
43: PCDATA invalid Char value 3
44: PCDATA invalid Char value 4
45: PCDATA invalid Char value 19
46: PCDATA invalid Char value 25
47: PCDATA invalid Char value 23
48: PCDATA invalid Char value 6
49: PCDATA invalid Char value 3
50: PCDATA invalid Char value 4
51: PCDATA invalid Char value 3
52: PCDATA invalid Char value 19
53: PCDATA invalid Char value 16
54: PCDATA invalid Char value 30
55: PCDATA invalid Char value 23
56: PCDATA invalid Char value 23
57: PCDATA invalid Char value 11
58: PCDATA invalid Char value 6
59: PCDATA invalid Char value 3
60: PCDATA invalid Char value 4
61: PCDATA invalid Char value 6
62: PCDATA invalid Char value 19
63: PCDATA invalid Char value 2
64: PCDATA invalid Char value 19
65: PCDATA invalid Char value 17
66: PCDATA invalid Char value 6
67: PCDATA invalid Char value 3
68: PCDATA invalid Char value 4
69: PCDATA invalid Char value 7
70: PCDATA invalid Char value 19
71: PCDATA invalid Char value 19
72: PCDATA invalid Char value 17
73: PCDATA invalid Char value 6
74: PCDATA invalid Char value 3
75: PCDATA invalid Char value 4
76: PCDATA invalid Char value 19
77: PCDATA invalid Char value 25
78: PCDATA invalid Char value 23
79: PCDATA invalid Char value 6
80: PCDATA invalid Char value 3
81: PCDATA invalid Char value 4
82: PCDATA invalid Char value 3
83: PCDATA invalid Char value 19
84: PCDATA invalid Char value 16
85: PCDATA invalid Char value 2
86: PCDATA invalid Char value 6
87: PCDATA invalid Char value 1
88: PCDATA invalid Char value 1
89: PCDATA invalid Char value 1
90: PCDATA invalid Char value 5
91: PCDATA invalid Char value 2
92: PCDATA invalid Char value 2
93: PCDATA invalid Char value 1
94: PCDATA invalid Char value 27
95: EntityRef: expecting ';'
96: PCDATA invalid Char value 3
97: PCDATA invalid Char value 18
98: PCDATA invalid Char value 16
99: PCDATA invalid Char value 20
100: xmlParseEntityRef: no name
101: PCDATA invalid Char value 6
102: PCDATA invalid Char value 6
103: PCDATA invalid Char value 8
104: PCDATA invalid Char value 21
105: PCDATA invalid Char value 5
106: PCDATA invalid Char value 2
107: PCDATA invalid Char value 22
108: PCDATA invalid Char value 26
109: PCDATA invalid Char value 5
110: PCDATA invalid Char value 4
111: PCDATA invalid Char value 28
112: PCDATA invalid Char value 3
113: PCDATA invalid Char value 8
114: PCDATA invalid Char value 22
115: PCDATA invalid Char value 17
116: PCDATA invalid Char value 28
117: PCDATA invalid Char value 30
118: PCDATA invalid Char value 27
119: PCDATA invalid Char value 31
120: PCDATA invalid Char value 12
121: PCDATA invalid Char value 23
122: error parsing attribute name
123: attributes construct error
124: Couldn't find end of Start Tag <ee> line 3446
125: PCDATA invalid Char value 2
126: PCDATA invalid Char value 6
127: PCDATA invalid Char value 4
128: Opening and ending tag mismatch: Journal line 3416 and AbstractText
129: Opening and ending tag mismatch: Article line 3415 and Abstract
130: Opening and ending tag mismatch: MedlineCitation line 3403 and Article
131: Opening and ending tag mismatch: PubmedArticle line 3402 and MedlineCitation
132: Opening and ending tag mismatch: Article line 1597 and PubmedArticle
133: Opening and ending tag mismatch: MedlineCitation line 1590 and PubmedArticleSet
134: Premature end of data in tag PubmedArticle line 1589
135: Premature end of data in tag PubmedArticle line 443
136: Premature end of data in tag PubmedArticleSet line 3

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

--- re-building ‘easyPM_vignette_pdf.Rmd’ using rmarkdown
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: 0xF0 0x33 0x60 0xC4
2: PCDATA invalid Char value 12
3: Opening and ending tag mismatch: ArticleIdList line 935 and ReferenceList
4: Opening and ending tag mismatch: Reference line 933 and PubmedData
5: Opening and ending tag mismatch: ReferenceList line 746 and PubmedArticle
6: Opening and ending tag mismatch: AbstractText line 1616 and AffiliationInfo
7: Opening and ending tag mismatch: Abstract line 1615 and Author
8: expected '>'
9: Opening and ending tag mismatch: ForeName line 1623 and ForeNbert
10: Opening and ending tag mismatch: Author line 1621 and Affiliation
11: Opening and ending tag mismatch: Article line 1596 and AffiliationInfo
12: Opening and ending tag mismatch: MedlineCitation line 1589 and Author
13: Opening and ending tag mismatch: PubmedArticle line 1588 and AuthorList
14: Opening and ending tag mismatch: PubmedData line 704 and Article
15: Opening and ending tag mismatch: PubmedArticle line 443 and MedlineCitation
16: PCDATA invalid Char value 12
17: Opening and ending tag mismatch: PubmedArticleSet line 3 and PubmedArticle
18: 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