Reference manual and Reference work

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

Reference work and reference manual are semantically related in reference book topic. In some cases you can use "Reference work" instead a noun phrase "Reference manual".

Reference work noun - A book to which you can refer for authoritative facts.

Reference manual and reference work are semantically related in reference book topic. You can use "Reference manual" instead a noun phrase "Reference work".