How may I avoid double payment of insurance contributions for a self-employed also earning an income under the "Order of classification of insured employed" (eg: a self-employed also working as a lecturer in a college)?

The self-employed whose income partially fall under the "Order of classification of insured employed workers" (in Hebrew) need to send us a Form 857: "Certificate of income tax deduction from taxable payments at source". The amount approved for deductions, for which insurance contributions were paid under the Order of insured classification, will be deducted from the income appearing in the tax return as self-employed, thereby avoiding double payment of insurance contributions on the same income.