The submission cannot have been previously published in English (but see below regarding conference papers), nor can it be before another journal for consideration. If the submission is based on a conference paper, the conference paper requirements in Author Guidelines - Article Preparation must be met. Previous publication in another language should also be disclosed. Such statements, along with explanations for exceptions to the above rules, should be included in the 'Comments to the Editor' section (for online submission), or in the covering letter (for email submission).