Is this a scientific Stealing or Not?
In 1746, Jean-Baptiste le Rond d’Alembert discovered the wave equation 1D wave equation: 
and within ten years, Euler discovered wave equation in 3D. In 19’th centaury, Maxwell’s equations were written, and stage was set for a new discovery. In 1942, Hannes Alfven showed that the Maxwell’s equations together with fluid equations allowed a wave solution. Wave was later called as Alfvén waves. His work was initially disputed by many leading scientists of the time.
In 1970, Hannes Alfven received the Nobel Prize in physics for his work.
So, here is a question:
After Alfven discovered his waves in 1942, his work was not recognized for several years. If during this time, someone who he talked about his physics, had published a numerical work, where wave motions or their effects could have been seen, and claimed the discovery and did not cite Alfven’s work:
Will this be considered a stealing?