Per Year

 @article{siagents-ieeecn6,
    booktitle = {Special Issue on Software Agents},
    editor = {Ganzha, Maria and Paprzycki, Marcin and Omicini, Andrea},
    journal = {Computing Now},
    month = nov,
    number = 11,
    publisher = {IEEE Computer Society},
    title = {Special Issue on Software Agents},
    url = {https://www.computer.org/publications/tech-news/computing-now/software-agents-twenty-years-and-counting},
    volume = 6,
    year = 2013
} 

 @article{agents-ieeecn6,
    author = {Ganzha, Maria and Paprzycki, Marcin and Omicini, Andrea},
    journal = {Computing Now},
    month = nov,
    number = 11,
    publisher = {IEEE Computer Society},
    title = {Software Agents: Twenty Years and Counting},
    url = {https://www.computer.org/publications/tech-news/computing-now/software-agents-twenty-years-and-counting},
    volume = 6,
    year = 2013
}