function Link(link)
  local target = link.target
  if string.sub(target, 1, 1) == '#' then
    local label = string.sub(target, 2)
    local ref_by_page = pandoc.RawInline('latex', 'page \\#\\pageref{' .. label .. '}')
    local note_content = pandoc.Para({pandoc.Str('See on '), ref_by_page, pandoc.Str('.')})
    local footnote = pandoc.Note(note_content)
    link.content:insert(footnote)
    return link.content
  end
end

function Span(span)
  local id = span.identifier
  if span.identifier then
    return { pandoc.RawInline('latex', '\\label{' .. id .. '}'), span }
  end
end