Landmark and Reference manual

Landmark noun - A point in a chain of events at which an important change (as in one's fortunes) occurs.

Reference manual and landmark are semantically related in reference guide topic. In some cases you can use "Reference manual" instead a noun "Landmark".

Reference manual noun - A manual containing information organized in a summary manner.

Landmark and reference manual are semantically related in reference guide topic. Sometimes you can use "Landmark" instead a noun phrase "Reference manual".