diff --git a/docs/examples/inversion/PyIRoGlass_Inversion.ipynb b/docs/examples/inversion/PyIRoGlass_Inversion.ipynb
index d926298d..f710b7d4 100644
--- a/docs/examples/inversion/PyIRoGlass_Inversion.ipynb
+++ b/docs/examples/inversion/PyIRoGlass_Inversion.ipynb
@@ -217,15 +217,15 @@
    "source": [
     "\n",
     "mest_5200, covm_est_5200, covepsilon_5200 = pig.inversion(tau_5200, epsilon_5200, sigma_tau_5200, sigma_epsilon_5200, intercept_zero=False)\n",
-    "mls_5200, covls_5200 = pig.least_squares(tau_5200, epsilon_5200, sigma_tau_5200, sigma_epsilon_5200)\n",
+    "mls_5200, covls_5200 = pig.least_squares(tau_5200, epsilon_5200, sigma_epsilon_5200)\n",
     "E_calib_5200, see_5200, r2_5200, rmse_5200, rrmse_5200, ccc_5200 = pig.inversion_fit_errors(tau_5200, epsilon_5200, mest_5200, covm_est_5200, covepsilon_5200)\n",
     "\n",
     "mest_4500, covm_est_4500, covepsilon_4500 = pig.inversion(tau_4500, epsilon_4500, sigma_tau_4500, sigma_epsilon_4500, intercept_zero=False)\n",
-    "mls_4500, covls_4500 = pig.least_squares(tau_4500, sigma_tau_4500, epsilon_4500, sigma_epsilon_4500)\n",
+    "mls_4500, covls_4500 = pig.least_squares(tau_4500, sigma_tau_4500, sigma_epsilon_4500)\n",
     "E_calib_4500, see_4500, r2_4500, rmse_4500, rrmse_4500, ccc_4500 = pig.inversion_fit_errors(tau_4500, epsilon_4500, mest_4500, covm_est_4500, covepsilon_4500)\n",
     "\n",
     "mest_3550, covm_est_3550, covepsilon_3550 = pig.inversion(tau_3550, epsilon_3550, sigma_tau_3550, sigma_epsilon_3550, intercept_zero=False)\n",
-    "mls_3550, covls_3550 = pig.least_squares(tau_3550, epsilon_3550, sigma_tau_3550, sigma_epsilon_3550)\n",
+    "mls_3550, covls_3550 = pig.least_squares(tau_3550, epsilon_3550, sigma_epsilon_3550)\n",
     "E_calib_3550, see_3550, r2_3550, rmse_3550, rrmse_3550, ccc_3550 = pig.inversion_fit_errors(tau_3550, epsilon_3550, mest_3550, covm_est_3550, covepsilon_3550)\n",
     "\n",
     "mest_1635, covm_est_1635, covepsilon_1635 = pig.inversion(tau_1635, epsilon_1635, sigma_tau_1635, sigma_epsilon_1635, intercept_zero=False)\n",
@@ -233,7 +233,7 @@
     "E_calib_1635, see_1635, r2_1635, rmse_1635, rrmse_1635, ccc_1635 = pig.inversion_fit_errors(tau_1635, epsilon_1635, mest_1635, covm_est_1635, covepsilon_1635)\n",
     "\n",
     "mest_carbonate, covm_est_carbonate, covepsilon_carbonate = pig.inversion(eta, epsilon_carbonate, sigma_eta, sigma_epsilon_carbonate, intercept_zero=False)\n",
-    "mls_carbonate, covls_carbonate = pig.least_squares(eta, epsilon_carbonate, sigma_eta, sigma_epsilon_carbonate)\n",
+    "mls_carbonate, covls_carbonate = pig.least_squares(eta, epsilon_carbonate, sigma_epsilon_carbonate)\n",
     "E_calib_carbonate, see_carbonate, r2_carbonate, rmse_carbonate, rrmse_carbonate, ccc_carbonate = pig.inversion_fit_errors(eta, epsilon_carbonate, mls_carbonate, covls_carbonate, covepsilon_carbonate)\n"
    ]
   },