Error(s) in re-building vignettes:
  ...
--- re-building ‘Spectral_analysis_sleep_electroencephalography.Rmd’ using rmarkdown
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                                 Dload  Upload   Total   Spent    Left  Speed

  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
  0  633M    0  991k    0     0  1303k      0  0:08:17 --:--:--  0:08:17 1303k
  0  633M    0 5759k    0     0  3240k      0  0:03:20  0:00:01  0:03:19 3241k
  3  633M    3 20.5M    0     0  7617k      0  0:01:25  0:00:02  0:01:23 7617k
 10  633M   10 68.4M    0     0  18.2M      0  0:00:34  0:00:03  0:00:31 18.2M
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 50  633M   50  320M    0     0  41.3M      0  0:00:15  0:00:07  0:00:08 60.1M
 60  633M   60  383M    0     0  43.8M      0  0:00:14  0:00:08  0:00:06 63.1M
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 91  633M   91  580M    0     0  49.3M      0  0:00:12  0:00:11  0:00:01 63.6M
100  633M  100  633M    0     0  50.4M      0  0:00:12  0:00:12 --:--:-- 65.0M
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                                 Dload  Upload   Total   Spent    Left  Speed

  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
100  153k  100  153k    0     0   630k      0 --:--:-- --:--:-- --:--:--  631k
Could not fetch http://www.zotero.org/styles/elsevier-with-titles
HttpExceptionRequest Request {
  host                 = "www.zotero.org"
  port                 = 80
  secure               = False
  requestHeaders       = []
  path                 = "/styles/elsevier-with-titles"
  queryString          = ""
  method               = "GET"
  proxy                = Nothing
  rawBody              = False
  redirectCount        = 10
  responseTimeout      = ResponseTimeoutDefault
  requestVersion       = HTTP/1.1
  proxySecureMode      = ProxySecureWithConnect
}
 (InternalException (HandshakeFailed (Error_Protocol "peer does not support Extended Main Secret" HandshakeFailure)))
Error: processing vignette 'Spectral_analysis_sleep_electroencephalography.Rmd' failed with diagnostics:
pandoc document conversion failed with error 61
--- failed re-building ‘Spectral_analysis_sleep_electroencephalography.Rmd’

--- re-building ‘Spindles_detection_and_analysis.Rmd’ using rmarkdown
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed

  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
100  153k  100  153k    0     0   550k      0 --:--:-- --:--:-- --:--:--  551k
Could not fetch http://www.zotero.org/styles/elsevier-with-titles
HttpExceptionRequest Request {
  host                 = "www.zotero.org"
  port                 = 80
  secure               = False
  requestHeaders       = []
  path                 = "/styles/elsevier-with-titles"
  queryString          = ""
  method               = "GET"
  proxy                = Nothing
  rawBody              = False
  redirectCount        = 10
  responseTimeout      = ResponseTimeoutDefault
  requestVersion       = HTTP/1.1
  proxySecureMode      = ProxySecureWithConnect
}
 (InternalException (HandshakeFailed (Error_Protocol "peer does not support Extended Main Secret" HandshakeFailure)))
Error: processing vignette 'Spindles_detection_and_analysis.Rmd' failed with diagnostics:
pandoc document conversion failed with error 61
--- failed re-building ‘Spindles_detection_and_analysis.Rmd’

--- re-building ‘Using_rsleep_and_SleepCycles_packages_to_detect_sleep_cycles.Rmd’ using rmarkdown
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed

  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
100  153k  100  153k    0     0   433k      0 --:--:-- --:--:-- --:--:--  435k
Could not fetch http://www.zotero.org/styles/elsevier-with-titles
HttpExceptionRequest Request {
  host                 = "www.zotero.org"
  port                 = 80
  secure               = False
  requestHeaders       = []
  path                 = "/styles/elsevier-with-titles"
  queryString          = ""
  method               = "GET"
  proxy                = Nothing
  rawBody              = False
  redirectCount        = 10
  responseTimeout      = ResponseTimeoutDefault
  requestVersion       = HTTP/1.1
  proxySecureMode      = ProxySecureWithConnect
}
 (InternalException (HandshakeFailed (Error_Protocol "peer does not support Extended Main Secret" HandshakeFailure)))
Error: processing vignette 'Using_rsleep_and_SleepCycles_packages_to_detect_sleep_cycles.Rmd' failed with diagnostics:
pandoc document conversion failed with error 61
--- failed re-building ‘Using_rsleep_and_SleepCycles_packages_to_detect_sleep_cycles.Rmd’

SUMMARY: processing the following files failed:
  ‘Spectral_analysis_sleep_electroencephalography.Rmd’
  ‘Spindles_detection_and_analysis.Rmd’
  ‘Using_rsleep_and_SleepCycles_packages_to_detect_sleep_cycles.Rmd’

Error: Vignette re-building failed.
Execution halted