The first half of the workbook includes chapter review material and tests for every unit. The second half of the workbook consists of student projects that are complete with detailed cutting and assembly instructions.
Books can be attributed to "Unknown" when the author or editor (as applicable) is not known and cannot be discovered. If at all possible, list at least one actual author or editor for a book instead of using "Unknown".
Books whose authorship is purposefully withheld should be attributed instead to Anonymous.