I guess you should contact the publishing house because as it also retains a copyright.

A copyright is a bundle of intellectual property rights granted to the creator of an original work. Copyrights are typically established by creating and registering the work. Copyrights provide exclusive right to the creator to use or authorize others to use their work. The reproduction in various forms, copying, printing, recording, public performance or adaptation are prohibited. This right provides economic right to the creator, that is the financial benefit for a lasting period of sixty years after the creator's death. A copyright is an automatic right that protects the creator of original works. Copyrights cover literary, dramatic, musical, artistic, and certain other intellectual works, both published and unpublished. Perhaps most important, a copyright gives the creator or first owner of such original work the legal right to control how the material can be used. Copyright comes into effect immediately upon the creation and recording in some way of a work. Having evidence that one created the work at a given time is also useful protection. Although not necessary, a work’s creator may register it with Copyright Office.

Thank you very much both Muhamed and Gousia for your useful information. And finally I have found that the author had granted to be used his tool freely before he died! I think now it is safe!!

All the Best