SetDirectory["C:\\drorbn\\AcademicPensieve\\Classes\\20-1350-KnotTheory"]

Make

Make::usage = "Make[targets, sources, Hold[action]] makes a target, or a list of targets, given sources, or a list of sources, in the style of the unix 'make' command.";
Make[target_String, sources_, action_Hold] := Make[Evaluate@{target}, sources, action];
Make[targets_, source_String, action__Hold] := Make[targets, Evaluate@{source}, action];
Make[targets_List, sources_List, action_Hold] := Module[{},
If[
(And @@ ((FileType[#] =!= None)& /@ sources)) &&
Or[
Or @@ ((FileType[#]===None)& /@ targets),
Min[AbsoluteTime[FileDate[#]]& /@ targets] < Max[AbsoluteTime[FileDate[#]]& /@ sources]
],
Print["Making ",targets, " ..."];
ReleaseHold[action]
]
];

Auto-fetch from DropBox

(*Make[target="20-1350-KnotTheory.pdf", source="C:\\Users\\drorb\\Dropbox\\Public\\20-1350-KnotTheory.pdf", Hold[
CopyFile[source, target, OverwriteTarget->True]
]]*)

Export

{
"TitleNotes" -> "This is my personal notebook for my 2021-22 <a href=http://drorbn.net/20-1350>MAT1350F Topics in Knot Theory</a> class. <span style=\"color: red;\">Use at your own risk.</span><p>",
"CleanTeX" -> True
}