89714
However , as properties such as brittleness of mild steel improved with better ferrous metallurgy and as steel became less costly to make thanks to the Bessemer process and the Siemens-Martin process , the use of wrought iron declined .
 Bessemer, Siemens-Martin
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Bessemer, Siemens-Martin